Sophia Abene is the assistant editor for 

. You can email her at abenes@mjhlifesciences.com.

Sophia Abene 

Climate change is increasingly recognized as a factor in spreading arboviruses, diseases transmitted by mosquitoes and ticks. Environmental factors like temperature, humidity, and precipitation patterns directly influence viruses such as dengue, Zika, chikungunya, and West Nile. As global temperatures rise, the range of mosquito vectors like 

, which carry these viruses, has expanded into previously cooler regions, heightening the risk of outbreaks in areas where these diseases were once rare.

Rising temperatures shorten the incubation period of viruses within mosquitoes, accelerating viral replication and increasing transmission rates. Studies have shown that higher temperatures significantly reduce the extrinsic incubation period (EIP) for diseases like dengue, thus enhancing transmission.

 study estimated that climate change accounts for 19% of the global rise in dengue cases, with temperatures increasing the speed of mosquito virus transmission. This research, covering 21 dengue-endemic countries, predicts a 40%-60% rise in global cases by 2050, with some regions, such as parts of Peru, Mexico, and Brazil, facing increases of up to 150%-200%.

As of 2024, 8,064 dengue cases in the United States have been reported. This data includes cases from US states and territories, with reports from 52 jurisdictions. The numbers are provisional and may be subject to change due to delays in reporting. Most cases in the US are linked to travel-related infections, although some local transmission has also been reported. Most are in warmer southern states such as Florida, Texas, Arizona, and Southern California.

In an exclusive email interview with an expert virologist who preferred anonymity emphasized, "The warmer the climate, the faster the virus replicates within the mosquito, increasing the chances of transmission." Climate-induced changes in rainfall patterns also create ideal breeding grounds for mosquitoes, while drought conditions can exacerbate breeding in stored water containers. These environmental shifts have already been linked to major dengue outbreaks in Southeast Asia and South America, often exacerbated by the El Niño phenomenon.

Urbanization, often driven by climate change, further contributes to the spread of arboviruses. Informal settlements in low- and middle-income countries, where poor waste management and water systems provide abundant mosquito breeding sites. The virologist pointed out, "Urbanization exacerbates the problem. In rapidly growing cities, especially in the Global South, inadequate waste management and water storage practices create ideal conditions for mosquito breeding.” The high population density in urban areas also facilitates virus transmission. Migration due to climate-related events such as floods and droughts has led to increased movement of populations into areas with new vectors, further elevating the risk of exposure to arboviruses.

Socioeconomic factors that amplify vulnerability to arboviruses are also worsened by climate change. Poverty, inadequate healthcare infrastructure, and limited access to clean water and sanitation are common in many regions affected by climate change, making it harder to control the spread of these diseases. In regions where the burden of arboviral diseases is already high, the lack of resources for vector control and outbreak response programs leads to increased morbidity and mortality.

The virologist stressed, "Poverty, lack of infrastructure, and poor healthcare systems create conditions where people are at much higher risk of infection. These regions simply don’t have the resources to deal with the rise in cases, especially with the added burden of climate change.”

The shifting landscape of arbovirus transmission presents significant challenges to public health. Traditional surveillance systems, which focus on static disease patterns, are ill-equipped to address the dynamic changes brought on by climate change. To address this, the investigator emphasized, "Current surveillance systems often fail to track the complex interactions between environmental change, vector biology, and disease spread. What we need is dynamic, integrated surveillance systems that use climate data and real-time epidemiological data to predict where outbreaks are most likely to occur." Integrating advanced technologies, including remote sensing, GIS, and AI, can significantly improve our ability to predict outbreaks and track vector populations.

Public health responses must be expanded to include enhanced vector control and innovative solutions like genetically modified mosquitoes and antiviral therapies. The virologist explained, "Genetic modification offers a transformative solution to controlling mosquito populations. Genetically modified mosquitoes carrying self-limiting genes can reduce the number of mosquitoes over time. Another promising method involves using mosquitoes infected with Wolbachia, a bacterium that prevents them from transmitting viruses like dengue and Zika."

Education and community engagement are also essential in controlling the spread of arboviruses. Public health campaigns should promote personal protection strategies, such as using insect repellent and bed nets, and encourage community-based initiatives to eliminate mosquito breeding sites. The virologist concluded, "Engaging communities is key to success. In many places, communities are already doing a lot to fight these diseases. We need to amplify that by providing them with more tools, knowledge, and support."

In conclusion, the impact of climate change on arboviral diseases represents an urgent and evolving threat to global public health. A comprehensive approach is required to mitigate these risks, including strengthened surveillance systems, innovative vector control strategies, public health education, and increased investment in healthcare infrastructure, especially in vulnerable regions. As climate change continues to reshape environmental and socioeconomic conditions, the virologist emphasized, "We need to take action now. We can’t afford to wait for the next outbreak. The time to act is now, with the right tools, strategies, and global coordination."

1. Mousavi FS, Shenagari M, Hashemnia SMR, Zandi M. Climate change and arboviruses: a growing threat to public health. 

(XX):1-10. doi:10.1016/j.nmni.2024.101532

2. Amid record year for dengue infections, new study finds climate change responsible for 19% of today’s rising dengue burden. Eurekalert press release. November 16, 2024. Accessed December 6, 2024.

https://www.eurekalert.org/news-releases/1063547

3. Current Year Data. CDC. November 14, 2024. December 6, 2024.

https://www.cdc.gov/dengue/data-research/facts-stats/current-data.html

Articles

Explore how climate change accelerates the spread of mosquito-borne diseases like dengue and Zika, highlighting innovative solutions, challenges, and the urgent need for global action.

Climate Change and Arboviral Diseases: An Escalating Global Health Threat

Close-up stainless ice scoop with ice cubes

This article first appeared in our sister publication 

reported that between 2021 and 2022, 23 cases of infections caused by 

 (sequence type ST659) were reported at 2 hospitals in southern California, attributed to contaminated ice and water from these machines. To manage the outbreak, health officials advised stopping the use of ice and tap water during clinical care activities, and an investigation is underway to identify the sources of contamination in the ice machines.

 is a gram-negative bacillus and part of the 

complex, known for causing opportunistic infections primarily in patients with cystic fibrosis, chronic granulomatous disease, and those who are immunocompromised. While central nervous system infections are rare, management is complicated by the bacterium's resistance to many antimicrobial agents.

In addition to the 23 cases reported in southern California, this study identifies 23 previously unreported infections of 

 ST659 between 2020 and 2024. This includes 13 cases at a northern California hospital, 8 at a hospital in Colorado, and 2 more at one of the southern California hospitals. All 4 hospitals used the same brand of ice machines and similar filters, descaling, and sanitizing products. 

 was isolated from samples collected from ice machines in 2 of these hospitals.

 ST659 between September 2020 and October 2021, with respiratory specimens as the source of infection in most patients.

: Reported 20 cases from August 2021 to July 2022, plus two additional cases from September 2022 to February 2023, with contamination found in ice and water samples from ice machines.

: Documented 3 cases between August 2021 and July 2022, but no 

 was isolated from ice machines, although 1 sample showed high bacterial levels.

: Identified 8 cases from April 2023 to February 2024, with 

 found in 6 of the 10 sampled ice machines during environmental testing.

According to the investigators, “The higher proportion of intra-abdominal specimens with 

 at hospital D is consistent with the observed practice at this hospital of directly applying refillable ice bags to abdominal surgical wounds and device insertion sites. High bacterial counts, such as that found in water samples from an ice machine at Hospital C, might also indicate risk of transmission of water-associated bacteria to patients.”

Whole genome sequencing was performed to evaluate the genetic similarity of the isolates. The analysis showed that all clinical and ice machine isolates were highly similar, with only 0 to 14 single nucleotide variant differences across 81% of the selected reference genome.

This report 2 two key limitations: the descaling and sanitizing products tested may have been from different lots used during patient exposures. Second, patient medical records do not document specific exposures to tap water and ice, making it difficult to confirm when and how these exposures occurred.

The findings indicate that during outbreaks of water-related organisms in health care facilities, staff should refrain from using tap water, and ice and water from ice machines for patient care.

Vazquez Deida AA, Spicer KB, McNamara KX, et al. 

 Infections Associated with Use of Ice and Water from Ice Machines for Patient Care Activities―Four Hospitals, California and Colorado, 2020–2024. 

Peralta DP, Chang AY, Ariza-Hutchinson A, Ho CA. 

 A rare yet emerging cause of bacterial meningitis. 

. 2018;11:61-63. Published 2018 Jan 9. Accessed October 9, 2024. doi:10.1016/j.idcr.2018.01.002

Contaminated ice machines caused Burkholderia multivorans infections at hospitals in California and Colorado. Health officials recommend stopping ice machine use during clinical care to prevent further outbreaks.

Health Care-Associated Burkholderia multivorans Infections Traced to Contaminated Ice Machines 

Gray spotted rooster and chicken in the farm garden on the grass looking for food.

The USDA’s Food Safety and Inspection Service (FSIS) has proposed new regulations to reduce 

 contamination in raw poultry. The rule, developed after a 3-year review, sets enforceable standards for specific 

serotypes in chicken and turkey to prevent contaminated products from entering the market.

Under the proposed rule, poultry products that exceed contamination thresholds for specific 

 for turkey, will be classified as adulterated under the Poultry Products Inspection Act (PPIA). This measure aims to enhance food safety and ensure that contaminated products do not reach consumers.

Contagion's exclusive interview with José Emilio Esteban, MD, PhD, the USDA's under-secretary for Food Safety, discusses the agency's strategy for implementing the new 

“The effectiveness can be monitored in many ways through our data collection systems. As for practicality, we've been engaging in very open collaboration with industry and consumer groups to arrive at this proposed document,” he continues, “We don’t want to increase the price; we want to maintain quality. We want to make sure that it’s safe. I truly believe there is a way to balance the improvements with a greater impact on consumer health.”

FSIS proposes additional regulatory updates requiring all poultry slaughter establishments to implement a microbial monitoring program (MMP) with statistical process control (SPC) methods. The revised regulations would mandate paired sampling at rehang and post-chill, which is designed to enhance pathogen control throughout the slaughter process.

Esteban, who worked for over 20 years at the USDA and 8 years at the CDC, is confident in the methodologies used to monitor and verify compliance.

“We’ve been monitoring that for years, so we have a very good baseline as to what the product looks like, specifically targeting 

, but also targeting microbial indicators,” he said. “The mechanisms are in place, so once this program goes into action, we’ll be able to measure prospectively what impact we’re making with every single sample we collect.” Knowing this is important, it reveals how the USDA plans to monitor compliance effectively, use data-driven methods for pathogen tracking, and implement the new standards progressively to ensure both impact and practicality across different plant sizes.

 serotypes of public health significance involved extensive monitoring and data comparison with the CDC. Serotypes causing illness and those identified in poultry were prioritized based on virulence.

Esteban explains, “We identified the serotypes that we are proposing as the top three to address. If we can control those three serotypes in chicken and turkey, we will be addressing about 25% of all the illnesses attributed to chicken. This was based on gene analysis from public data, risk assessments, and input from the CDC. We intend to revise that list every 3 to 5 years because, just like with people and food, pathogens also change over time.”

These serotypes were prioritized through monitoring various 

 serotypes for an extended period. All the data is uploaded to a publicly accessible genome database, NCBI. By comparing the 20 serotypes of concern listed by the CDC with the 20 serotypes identified by the USDA, they can target the serotypes that overlap between those causing illness and those found in poultry. After this comparison, they determined that while the overlap includes 8 or 9 serotypes, it is not feasible to address all of them simultaneously. Consequently, they decided to prioritize the most virulent serotypes for immediate attention.

This proposed rule builds on FSIS’ recent initiatives to enhance consumer protection under the Biden-Harris Administration. To develop this framework, FSIS has conducted extensive data gathering, risk assessments, and stakeholder consultations.

Esteban finalizes, “It’s not a big change; it’s a change in the way we approach things, going from a big hammer to a little hammer, trying to reduce all 

,” he continues. “By changing how we’re measuring and implementing controls, there won’t be a huge impact on industry, and there will still be a benefit for society.”

The USDA proposes a phased implementation of the new standards to ensure a transition. Large plants will meet the latest standards in the first year, followed by medium-sized producers in the second year, and very small producers in the third year. This approach allows for monitoring and adjustment. The USDA will focus on 

 serotypes to improve food safety and evaluate the rule’s effectiveness over time.

1. Salmonella Framework for Raw Poultry Products. Published August 7, 2024. USDA. Accessed August 8, 2024. 

https://www.fsis.usda.gov/policy/federal-register-rulemaking/federal-register-rules/salmonella-framework-raw-poultry-products

2. USDA. USDA Proposes New Policy to Reduce Salmonella in Raw Poultry Products. USDA. Published July 29, 2024. Accessed August 8, 2024. 

https://www.usda.gov/media/press-releases/2024/07/29/usda-proposes-new-policy-reduce-salmonella-raw-poultry-products

The USDA aims to enhance food safety and public health while maintaining cost-effectiveness and ensuring safer poultry products by implementing targeted monitoring and a phased compliance approach.


USDA Proposes New Regulations to Reduce Salmonella in Poultry

(This article was originally published by our sister publication 

Independence Day is a time for celebration with friends and family, often centered around outdoor picnics and barbecues. However, amidst the festivities, it is important to prioritize food safety to prevent foodborne illnesses.

Grilling is a beloved tradition on the fourth of July, but cooking food thoroughly to kill harmful bacteria is essential. 

, PharmD, Pharmacist/Toxicologist, and medical contributor for Drugwatch, provides insights into maintaining safety while enjoying the festivities,

“Since bacteria in food multiply faster at temperatures between 40 degrees F and 140 degrees F. Following the FDA Prevention Tips above and being aware of temperatures while picnicking or barbecuing are essential to avoid foodborne illness. Hamburgers should be cooked to 160 degrees F (brown all the way through), and chicken should be cooked to at least 165 degrees F. Keeping any materials that have come into contact with raw meat very clean is essential (avoiding cross-contamination!).”

It is essential to cook hamburgers to 160°F and chicken to at least 165°F to destroy all harmful bacteria.

Keep raw meats separate from ready-to-eat foods and clean all utensils and surfaces that come into contact with raw meat to avoid spreading bacteria.

Refrigerate leftovers within 2 hours (or 1 hour if the temperature is above 90°F) to prevent bacteria from multiplying and ensure food remains safe to eat.

Foodborne illness, commonly known as food poisoning, arises from consuming food contaminated with bacteria, toxins, parasites, viruses, chemicals, or other harmful agents. Despite the US boasting one of the safest food supplies globally, federal estimates indicate approximately 48 million cases of foodborne illness annually. This statistic translates to roughly 1 in 6 Americans falling ill from tainted food, leading to an estimated 128,000 hospitalizations and 3,000 deaths each year.

Fitzgerald advises, “To effectively eliminate harmful bacteria, common foodborne pathogens, the FDA recommends thorough handwashing with soap and water for at least 20 seconds (consider carrying moist disposable towelettes if running water is unavailable), keeping raw and cooked foods separate, marinating food in the refrigerator rather than on the counter, using a food thermometer to ensure thorough cooking, promptly refrigerating or freezing food (avoid leaving food out of coolers or off the grill for more than 2 hours; 1 hour in temperatures exceeding 90°F), and maintaining hot foods at or above 140°F and cold foods at or below 40°F.”

Foodborne illness occurs when individuals ingest food or drinks contaminated with pathogens, chemicals, or toxins. Factors such as a weakened immune system or age can exacerbate the severity and symptoms of food poisoning.

“When reheating food, it should reach 165 degrees F, and foods like chicken salad and desserts should be kept in individual serving dishes and placed directly on ice or in a shallow container set in a deep ice-filled pan. A little extra preparation before a fun event can keep you and summer party-goers healthy for the whole season,” emphasizes Fitzgerald.

Adhering to these guidelines will guarantee that your July Fourth BBQ is delicious and safe for everyone to enjoy. Taking these precautions with food handling and cooking temperatures will significantly reduce the risk of foodborne illnesses, ensuring a memorable celebration.

FDA. Foodborne Pathogens. Updated May 3, 2023. Accessed July 2, 2024. 

https://www.fda.gov/food/outbreaks-foodborne-illness/foodborne-pathogens#:~:text=Foodborne%20illness%20occurs%20when%20people,weakened%20immune%20system%20and%20age

Staying Safe on Independence Day: Food and Fireworks 

Measles—medical concept with blurred text, stethoscope, pills, and syringe on a blue background.

This article first appeared in our sister brand, 

 is the most contagious and easily transmittable virus we know—far more than COVID[-19] or influenza,” said Patricia A. Stinchfield, MS, RN, CPNP, president, National Foundation for Infectious Diseases (NFID).

This outbreak resulted in 57 confirmed cases, including residents, staff, and linked community members. The CDC employed dynamic disease modeling to forecast outbreak trajectories and evaluate the efficacy of public health interventions. Real-time, dynamic disease models proved invaluable in guiding public health responses, aiding in setting expectations regarding outbreak size and duration, and quantifying the effectiveness of interventions.

As of April 8, the model projected a median final outbreak size of 58 cases, with an interquartile range of 56–60 cases. The counterfactual analysis demonstrated the significant impact of early deployment of public health interventions, with mass vaccination and active case-finding reducing the likelihood of an outbreak exceeding 100 cases from 69% to 1%.

“If mass vaccination had been delayed by 1 week, there would have been an 8-fold increase (from 1% to 8%) in the chance of an outbreak of 100 or more cases over the scenario in which mass vaccinations were deployed on March 8," according to the CDC. "These results are consistent with those from the OAW response, in which a modeled 7-day delay in vaccination would have yielded a 50% increase in median outbreak size.”

's May Trending Topic: National Nurses Month

CDC employed a dynamic disease model, continuously updated as new cases emerged, to simulate the measles outbreak among shelter residents. This model allowed real-time forecasting of outbreak progression and enabled the assessment of various intervention strategies. A counterfactual analysis to compare outbreak scenarios with and without interventions, focusing on mass vaccination and active case-finding.

“This parameter emphasized the importance of active case surveillance because of the possibility of many secondary cases," according to the CDC. "CDPH used these findings, along with observed measles cases among shelter residents who had received a single dose of MMR vaccine, to demonstrate the need for continued vaccination campaigns during the outbreak, including a second dose campaign 28 days after the first dose and to recommend that shelter staff members and essential visitors provide evidence of immunity to measles.”

Despite efforts to control and eliminate measles, outbreaks can still occur, as in Chicago in 2024.

The article highlights the CDC's use of dynamic disease modeling to forecast outbreak trajectories and evaluate the effectiveness of public health interventions in real time.-

The surge in measles cases underscores the importance of maintaining high vaccination coverage rates and robust surveillance systems.

Despite its utility, the modeling approach had limitations. Due to the outbreak's limited size, parameters were subject to substantial uncertainty. Additionally, the model structure and assumptions may have influenced the accuracy of projections. The model did not account for the relocation of 22 family units to a quarantine hotel, potentially affecting final outbreak size estimations.

 elimination status was maintained due to the absence of sustained measles virus transmission for 12 consecutive months and the presence of a well-performing surveillance system. Despite this, widespread US measles transmission risk remains low due to high population immunity. The increase in cases during the first quarter of 2024 indicates that additional activities are needed to enhance routine measles, mumps, and rubella vaccination coverage, particularly among close-knit and under-vaccinated communities. These activities should include promoting vaccination before international travel and rapidly investigating suspected measles cases.

During the specified period, the CDC was notified of 338 confirmed measles cases. Notably, 97 (29%) of these cases occurred during the first quarter of 2024, representing a more than 17-fold increase over the mean number of cases reported during the first quarters of 2020 to 2023. Among the reported cases, the median patient age was 3 years, with ages ranging from 0 to 64 years. Most patients, 309 (91%), were unvaccinated or had unknown vaccination status. Additionally, 336 case investigations included information on 80% or more of critical surveillance indicators. From 2020 to 2023, the longest transmission chain lasted 63 days.

The findings underscore the role of proactive public health measures, such as prompt mass vaccination and active case-finding. While the study provides valuable insights, it also highlights the need for continued refinement and validation of modeling approaches in outbreak response.

Parkinson, J. Measles Outbreaks: How Complacency Associated With Immunizations and COVID-19 are Driving Increases. Contagion. Published February 24, 2024. Accessed May 23, 2024. 

https://www.contagionlive.com/view/measles-outbreaks-how-complacency-associated-with-immunizations-and-covid-19-are-driving-increases

Real-Time Use of a Dynamic Model To Measure the Impact of Public Health Interventions on Measles Outbreak Size and Duration — Chicago, Illinois, 2024. 

Morbidity and Mortality Weekly Report (MMWR). 

Published May 16, 2024. Accessed May 23, 2024. 

https://www.cdc.gov/mmwr/volumes/73/wr/mm7319a2.htm?s_cid=mm7319a2_w

Abene, S. Surge in Measles Cases Calls for Boost in Vaccination Efforts. 

. Published April 13, 2024. Accessed May 23, 2024. 

https://www.contagionlive.com/view/surge-in-measles-cases-calls-for-boost-in-vaccination-efforts

CDC's dynamic modeling and early mass vaccination effectively controlled a 2024 measles outbreak, highlighting the critical importance of vaccination and proactive public health measures.


Measles Outbreak Control: CDC's Dynamic Modeling and Mass Vaccination Strategies

 are collaborating on rare infectious diseases for Rare Disease Awareness Month, examining both old and new infectious diseases that health care workers need to know.

 poses a critical challenge to global health, linking parasitic infection complexities with climate change and public health inequities. The mosquito-transmitted infectious disease is caused by protozoan parasites of the 

 responsible for the most severe cases. This disease spreads through the bite of an infected mosquito, introducing the parasite into the human bloodstream. The significant presence of malaria in Africa is attributed to the Anopheles mosquitoes' long lifespan and preference for biting humans.

“Parasites are as complex; you can think of them as being as complex as a human cell. Because they code for 1000s of proteins, as opposed to viruses, which only have a minimal genome, they make only a handful of proteins,” Prakash Srinivasan, PhD, assistant professor, Johns Hopkins Malaria Research Institute said. “So, parasites are a lot more complex than viruses, and the reason why it becomes such a big challenge to develop vaccines against parasites, such as the malaria parasite plasmodium.”

Malaria remains a burden in sub-Saharan Africa, further exacerbated by climate change. Fluctuations in temperature and precipitation influence the disease's vectors and incidence rates (IR). A study in 

 outlines how average temperature changes affect malaria incidence rates in 9 sub-Saharan countries, noting a 20–80% decrease from 2000 to 2018. Malaria remains a significant public health concern in sub-Saharan Africa despite a marked decline in incidence rates observed in most of the countries studied.

This study aligns with recent findings, showing a 20 to 80% decrease in malaria IR from 2000 to 2018. However, there's significant variability in IR, with high rates in Uganda, Mozambique, Nigeria, and Zambia; moderate rates in Ghana, Zimbabwe, and Kenya; and low rates in South Africa and Ethiopia in 2018. It highlights how IR varies with average temperature changes in some countries and points out an inverse temperature-IR relationship, especially during periods of IR decrease in Ghana and Nigeria that matched with temperature increases. These decreasing IR trends, affected by temperature fluctuations, are likely shaped by intervention efforts and rainfall changes. Yet, the threat of vulnerability and changing climate may challenge further reductions in malaria IR.

“Malaria represents an emblematic example of how climate change can directly influence human health, facilitating the spread of infectious diseases previously confined to well-defined geographical areas,” said Mariana Torres, MD, head of surveillance at BlueDot. “Responding to this challenge requires a coordinated approach that includes environmental monitoring, vector control, research and development of new diagnostic and therapeutic tools, and public information and awareness campaigns.”

Symptoms, Prevention, and Recent Advancements

The CDC monitors malaria as it becomes more prevalent in the US, emphasizing the risk of severe health issues and fatalities if untreated. In 2020, there were 241 million global instances and 627,000 deaths, mostly among young children in sub-Saharan Africa.

Symptoms of malaria typically emerge 10 to 15 days after a bite from an infected mosquito, and early testing is crucial due to the potential for some malaria strains to lead to serious health complications or death. High-risk groups include infants, children under 5, pregnant women, travelers, and individuals with HIV or AIDS. Critical symptoms encompass severe fatigue, loss of consciousness, repeated seizures, breathing difficulties, discolored or bloody urine, yellowing of the skin (jaundice), and unusual bleeding. Immediate medical attention is necessary for those experiencing severe symptoms. Malaria in pregnant women can result in early delivery, stillbirth, or the birth of an underweight infant. Prevention strategies include mosquito bite avoidance and prophylactic medication, while treatments exist to prevent the progression of mild cases.

Hernán Acosta, MD, internal medicine specialist and clinical lead at BlueDot, notes the importance of vector control and early diagnosis in endemic areas, highlighting challenges like insecticide resistance.

“While highly endemic areas focus on vector control as well, they implement insecticide-treated nets and indoor residual spraying as part of disease control and elimination strategies. However, the increase in insecticide resistance among the Anopheles mosquitoes requires urgent action to maintain and improve malaria control efforts,” Acosta said. “Early diagnosis and treatment and preventive chemotherapy are also part of the population-based strategy in endemic areas. The latter focuses on the use of antimalarial medication during pregnancy, infancy, and in children living in high-risk areas per WHO guidelines.”

The approval and deployment of RTS, S/AS01, and R21/Matrix-M vaccines represent a milestone in malaria control, potentially saving about 450,000 lives a year. With 80 million children eligible for vaccination in sub-Saharan Africa, doses are highly needed. The availability of these vaccines offers at-risk children protection against malaria.

The World Health Organization (WHO) has approved 2 vaccines, RTS, S (Mosquirix) and R21/Matrix-M, marking significant progress in malaria control. These vaccines promise to reduce the disease's impact, with the R21/Matrix-M vaccine demonstrating up to 75% efficacy.

for the R21/Matrix-M vaccine, involving 4,800 children in Burkina Faso, Kenya, Mali, and Tanzania, demonstrated that the vaccine was safely tolerated and had a positive safety profile. Over 12 months, the vaccine showed an efficacy rate of 75% in regions with high seasonal malaria transmission and 68% in areas with perennial transmission. It was also observed that administering a booster dose significantly improved its effectiveness, maintaining a 74% efficacy rate over 18 months in seasonal transmission areas.

 have been deemed safe and effective in preventing malaria in children, who are disproportionately affected, especially in regions such as Africa, where nearly 500,000 children die each year from the disease.

“Demand for the RTS, S vaccine far exceeds supply, so this second vaccine is a vital additional tool to protect more children faster and to bring us closer to our vision of a malaria-free future," said WHO Director-General Tedros Adhanom Ghebreyesus in a statement.

Based on data from an ongoing clinical trial and other studies, the R21 vaccine has been shown to have a high degree of efficacy when administered just before the high transmission season, with data showing a 75% reduction in malaria cases in the 12 months following the 3-dose series. A fourth booster dose administered 1 year later helped maintain efficacy.

Travelers to malaria-endemic regions face varied risks, necessitating personalized prevention strategies. Despite the approximately 2000 annual US cases of travelers' malaria, local transmission remains rare, thanks to environmental conditions and mosquito behaviors.

Malaria in the US is primarily associated with travelers' malaria. This includes people visiting from malaria-endemic countries or US residents who travel to countries with ongoing transmission. Upon their return, they may already be infected, bringing the parasites back with them and starting to show symptoms, according to Prakash Srinivasan, PhD." “So that's what is called travelers malaria. And usually, there are about 2000 cases of travelers malaria every year in the US. But this year, after almost 2 decades, of no local transmission of malaria.”

, the CDC posted a health advisory on its website that stated that 5 cases of malaria were identified in the continental United States. There were 4 individual cases in Florida and 1 case diagnosed in Texas within the last 2 months.

Efforts to combat malaria through improved understanding, prevention, and treatment are making headway, with vaccines offering a new tool for reducing its impact. However, continued efforts in mosquito control, public health education, and international cooperation are essential. The fight against malaria exemplifies the importance of research, innovative solutions, and global collaboration in addressing infectious diseases.

The development of vaccines represents significant progress in combating malaria. Climate change alters malaria's spread, requiring adaptable public health strategies. The battle against malaria emphasizes the need for continued research, international collaboration, and innovative solutions to mitigate the threat of malaria. Combining scientific developments with prevention strategies is essential for reducing and potentially eradicating the impact of malaria.

Malaria. WHO | Regional Office for Africa. Accessed February 21, 2024. 

https://www.afro.who.int/health-topics/malaria

Leal Filho W, May J, May M, Nagy GJ. Climate change and Malaria: Some Recent Trends of Malaria Incidence Rates and Average Annual Temperature in Selected Sub-Saharan African Countries from 2000 to 2018. 

. Published August 28, 2023. Accessed February 21, 2024. doi:10.1186/s12936-023-04682-4

Datoo M, Dicko A, Tinto H, Ouédraogo J, Hamaluba M, et. al. Safety and Efficacy of Malaria Vaccine Candidate R21/Matrix-M in African children: a Multicentre, Double-Blind, Randomised, Phase 3 Trial. Published February 1, 2024. Accessed February 21, 2024. doi: 

https://doi.org/10.1016/S0140-6736(23)02511-4

Prevention CC for DC and. Cdc - Malaria - Diagnosis & Treatment (United States) - treatment (US) - Guidelines for Clinicians (Part 1). Published June 28, 2023. Accessed February 21, 2024. 

https://www.cdc.gov/malaria/diagnosis_treatment/clinicians1.html

Bigicia, A. New Malaria Vaccine Endorsed by WHO Could Help Resolve Supply Issues. 

Published October 6, 2023. Accessed February 21, 2024. 

https://www.contagionlive.com/view/new-malaria-vaccine-r21-matrixm-endorsed-by-who-could-help-resolve-supply-issues

Parkinson, J. The CDC Sends Out Health Advisory on Locally Acquired Malaria Cases in Continental US. 

Published June 27, 2023. Accessed February 21, 2024. 

https://www.contagionlive.com/view/the-cdc-sends-out-health-advisory-on-locally-acquired-malaria-cases-in-continental-us

Dive into the intricate world of malaria, from parasite complexities to climate change, and the latest in vaccination, vital knowledge for health care workers.