Vaccination of Children and Adults from Yellow Fever

The Centers for Disease Control suggests that anyone between the ages of 9 months and 59 years old and traveling to or living in an area where the risk of yellow fever is present should be vaccinated. In urban areas, the focus should be on eliminating mosquito populations and breeding sites in various ways such as applying larvicides to water storage containers and other places where standing water collects. The World Health Organization recommends that every at-risk country have at least one national laboratory where tests to detect yellow fever can be performed. Community involvement in activities such as cleaning household drainage and adequate coverage of water-filled containers where mosquitoes tend to develop is a very important and efficient method of mosquito control. Using repellents approved by health authorities is a prevention option, as well as the use of long-sleeved shirts and trousers for people going into the jungle or forest. (I would also include avoiding going to these places altogether as a form of prevention.) In urban areas, it is important to use mosquito nets in windows and doorways to prevent mosquitoes from entering the houses.

Annually, there are around 200,000 cases of yellow fever with approximately 90% of them occurring in Africa. Since the 1980s, there has been a dramatic resurgence of yellow fever in both sub-Saharan Africa and South America. A series of epidemics and smaller outbreaks of yellow fever that occurred in West African countries were primarily responsible for the increased incidence of yellow fever in Africa, but the first epidemic reported in Kenya in over to decades signaled a change in the distribution of the disease was also occurring. In Africa, Yellow Fever is a significant problem because transmission is easily carried out due to large mosquito populations inhabiting towns and cities with many unvaccinated individuals

Although some countries have incorporated the yellow fever vaccine into childhood immunization programs, the vaccine coverage offered is not optimal. The efficacy of a good vaccination program can be seen in the transmission rates of South America, which are lower than those in Africa, in part because of the mass immunization campaigns responding to the outbreaks of Yellow Fever. South America experienced its largest outbreak of Yellow Fever since the 1950s in 1995, in Peru. Shortly thereafter, mass outbreaks in Brazil prompted mass vaccination campaigns. Low vaccine coverage contributed to these outbreaks and subsequent vaccination campaigns have succeeded in lowering the prevalence of Yellow Fever in South America. In addition, migration of susceptible individuals to forested regions and increased urbanization also played a role.

To further boost immunization and inclusion of the Yellow Fever vaccine in the regimen of children in targeted African and Latin American countries, The Yellow Fever Initiative implements mass vaccination campaigns focused on high-risk areas while monitoring the disease and outbreak response capacity while also boosting vaccine production to meet global demand.

A comprehensive risk assessment allows countries to identify population groups for prioritized vaccination. Each year, six million available doses are stockpiled for emergency response. This stockpile has been instrumental in controlling yellow fever outbreaks in Africa and the Americas and in possible preventing epidemics In addition, high-risk countries in Africa are being provided over 230 million doses. Additional resources and flexibility will allow preventative strategies to be implemented more efficiently, allow for better responses to outbreaks, and will allow for the expansion of such policies to other countries and territories.