Tropical Health Matters

Malaria is one of the more than 30 diseases and conditions included in the Elimination Initiative and targeted for elimination in the Region of the Americas by 2030. Colombia provides a useful example of the progress and challenges. Of the over 72,000 reported malaria cases in 2022, About 61% were caused by P. vivax, 38% by P. falciparum, and 1% were mixed. The Ministry of Health explains that unlike other South American countries, the most malaria endemic regions are not in the Amazonian forest but lie in the northwest of the country in the Pacific coastal forests, populated by Afro-Colombian and indigenous communities.

The Ministry also notes that malaria transmission is characterized by the presence of epidemic cycles that occur every 2 to 7 years, related to the occurrence of the Niño-Southern Oscillation phenomenon. Malaria control is particularly challenging in provinces where illegal mining, logging and the growing of illicit crops are conducted. The World Malaria Report of 2023 traced annual malaria trends in Colombia and showed a peak in 2018-19 with a reduction in subsequent years that points toward efforts at elimination

The International Rescue Committee identifies a particular challenge for Colombia. At least 4 million Venezuelans have crossed the border to seek refuge, and that number continues to rise. Venezuela continues to be plagued by malnutrition, lack of medical supplies, high homicide rates and the spread of diseases such as malaria and measles. Since outbreaks of measles, diphtheria and malaria have been reported across Venezuela, it would be surprising that refugees would enter Colombia with malaria infections.

A study of malaria among migrants in a university hospital in Colombia during 2018 found that imported malaria has increased in Colombia since 2015 and has been attributed to migrants coming from Venezuela. To address the challenge, we need to know where are the refugees? Regular migration is usually located in the main cities and in places where tourism or the mining industry are active. Many of the destinations are in areas where malaria is not endemic, onward transmission would be less likely. Unfortunately, the following migration destinations overlap with malaria transmission: Nariño, Antioquia, Cundinamarca, Cauca, and Chocó, such that those migrants can acquire new infections.

The challenge is that as Colombia makes progress toward eliminating malaria, it still must maintain high capacity to tackle imported cases as well as new cases among a particularly vulnerable refugee population.

Bradley Blankenship contributed a blog posting on the continued challenges of Dengue in Brazil for the course, “Social & Cultural Basis for Community and Primary Health Programs,” at the Johns Hopkins Bloomberg School of Public health. Below are his concerns and observations.

A child receiving the dengue vaccine in Brazil, courtesy Nature.com

Brazil is currently facing a record-breaking number of dengue cases. In 2024, the country reported 5.1 million cases, with over 2,800 deaths associated with dengue. This is an all-time high for the country and surpasses projections. As a response, the government attempted changes to its national immunization program with the implementation of the Qdenga vaccine (Takeda’s new dengue vaccine). In fact, Brazil secured the entire global supply of Qdenga in 2024 to address rising numbers of cases and complications. This campaign is a crucial step for Brazil, but it is not without its challenges.

Safety and trust are major issues with new Dengue vaccine rollouts, as Qdenga follows a controversy in the Philippines after a previous vaccine, Dengvaxia, was withdrawn when it was found to increase the risk of severe Dengue in dengue-naïve children. This controversial rollout eroded public confidence in dengue vaccines. In contrast, Qdenga has been proven safe, even for those who have never been infected, and does not require pre-vaccination testing. This is a critical advantage of Qdenga and a crucial point to consider when rebuilding trust.

The global supply of Qdenga is limited, though, and Takeda is only able to produce about 6 million doses each year. This means that only 3 million people may receive the two-dose series recommended by the developers. The initial campaign, therefore, only covers a fraction of Brazil’s population. Furthermore, two-dose uptake by the population is also a concern, with only 714,000 reported second doses administered vs 2.16 million first doses reported, underlining the need for better follow-up and public education.

Moving forward, we need the Brazilian Ministry of Health to act on multiple fronts to address the dengue outbreak in Brazil. We need expanded access to Qdenga vaccines by securing more doses and broadening eligibility, rebuilding vaccine trust and compliance through education and community partnerships, and further support for the development of single-dose vaccine being developed by the Butantan Institute that would allow for improved compliance and domestic production, ultimately securing the ability to produce more vaccines as needed.

With millions of Brazilians vulnerable to dengue fever, decisive leadership from Brazil’s Ministry of Health is essential to adequately address the outbreak.

This brief posting is an abstract from a Capstone Project for the Master of Public Health Degree at the Johns Hopkins Bloomberg School of Public Health by Lauren Akua Koranteng.

Based on evidence globally, cancer is a leading cause of death, with significant disparities in low- and middle-income countries like Ghana, West Africa, where breast, liver, and cervical cancers are common. According to the Global Cancer Observatory, in 2022, the three leading causes of cancer in Ghana for both sexes were cancers of the breast, liver and cervix. Out of a population of over thirty-two million, there were 27,385 new cases, and the number of deaths was 17, 944.

This study assesses the readiness of Ghanaian health facilities to deliver cancer services using 2022 data from the WHO Harmonized Health Facility Assessment (HHFA). The analysis included 1,421 facilities across all sixteen regions in the nation, evaluating service availability, staff training, and resource allocation for cervical, breast, prostate, and colorectal cancers.

The results found that cancer services were discovered to be the lowest service availability among the noncommunicable disease (NCDs) with 17% of facilities offering cancer services. Cervical cancer services were very minimal, with 5% of facilities providing pap smears and 1% offering colposcopy procedures. Breast cancer services were slightly higher (15%). However, mammography was mostly unavailable in the various regions. Prostate and colorectal cancer were extremely low at 5% and 1%, respectively.

Greater Accra had the highest service availability (38% for any cancer), while regions like the Savannah region fell behind (14%). The government and regional hospitals have better resources and infrastructure in comparison to the community-based CHPS compounds.

In conclusion, several gaps exist in the nation with inadequate staff training and low drug availability (e.g., 3% tamoxifen) and a lack of national cancer registries. Based on these gaps in service availability, staff training, and resources, it would be best to recommend the prioritization of regional hospitals as cancer care centers, and a drive to expand the workforce in those areas to better manage cancer care in the nation.

Another recommendation would be to introduce HPV vaccinations and implement national screening programs. This will help to assist with meeting Ghana’s Universal Health Coverage goals and reduce cancer deaths.