Pathogenesis of Emerging and Re-emerging Diseases
Yellow fever
Yellow fever is a mosquito-transmitted ailment of the epidemic variety that can be prevented by vaccination. This disease is transmitted to humans through the bites of infected mosquitoes. It is now an important global public health problem, especially in tropical and subtropical regions. Symptoms include fever, myalgia, headache, anorexia, and nausea or vomiting. Yellow fever is common in Africa as well as Central and South America. There are no specific medical drugs for yellow fever, but its symptoms are addresse
- A combination of Polymerase Chain Reaction (PCR), Enzyme-Linked Immunosorbent Assay (ELISA), and Hemagglutination Inhibition (HI) are used in diagnosing yellow fever (World Health Organization, 2023). It was recommended that the prevalence be reduced using vaccines, vector control, and personal protection methods, among others. The recommendations indicate the need for comprehensive strategies against this very contagious disease.
Origin of the infectious disease
Yellow fever is a disease caused by an arbovirus transmitted to people by infected mosquitoes in subtropical and tropical regions of Africa, South America, and Central America. Aedes and Haemagogus mosquito species spread the virus and are commonly
found in tropical and subtropical parts of Africa and South America (World Health Organization, 2023). The virus is sustained in a “zoonotic cycle,” where it exists in two distinct hosts – humans as well as non-human primates.
Pathogenesis/microbiologic classification of the microorganism
A Flavivirus arbovirus from the Flaviviridae family brings on yellow fever. The virus is a single-stranded RNA virus with a positive polarity. The mosquitoes in question are Aedes simpsaloni, A. The virus is composed of three structural proteins: envelop (E) protein, membrane (M) protein, and capsid (C) protein. The E protein harbors primary epitopes for antibody neutralizers that aid in attaching to host cells and entering them. The M protein regulates the replication process in a host cell, whereas the C protein is responsible for packaging its genetic material to generate virions. Human infection starts when viral particles are deposited through the skin by infected arthropod saliva.
Occurrences of the disease local, national, and global
Yellow fever is a significant and dangerous disease that poses a risk of spreading internationally, making it an imminent danger to global health safety. It is common in tropical and subtropical regions of Africa and South America. In 2023, 34 African countries and 13 Central and South American countries are endemic for yellow fever or have locations where the disease is prevalent (World Health Organization, 2023). There are almost 200,000 cases of yellow fever each year, leading to 30,000 deaths. Yellow fever outbreaks have intermittently affected regions in Asia, Oceania, and the Caribbean. The majority of cases are focused on Africa, particularly in countries with limited healthcare systems and limited access to immunization.
Diverse populations affected by this disease
The virus is prevalent in tropical regions of Africa as well as South and Central America. Significant outbreaks of yellow fever arise when infected individuals bring the virus into densely populated regions with abundant mosquitoes and where the majority of people lack protection, sometimes due to the absence of immunization. Yellow fever affects people of all age groups and ethnicities, with infants under nine months, pregnant women, individuals with severe egg protein
allergies, and those with severe immunodeficiency being particularly vulnerable to severe illness and death.
Incubation period; period of communicability; methods used for diagnosis; treatment including antimicrobials
The incubation period for yellow fever usually ranges from 3 to 6 days, whereas the period of communicability extends from 1 to 2 days before symptoms appear to 7 to 10 days after symptoms start (World Health Organization, 2023). Yellow fever symptoms consist of fever, headache, myalgia, nausea, vomiting, and
| jaundice. Diagnosis is usually conducted by blood testing. There is no targeted treatment for yellow fever. However, supportive care can be administered to alleviate symptoms. Antiviral drugs can be provided to lessen the seriousness and length of the sickness.
Applicable laboratory testing used to detect immunity The ELISA (Enzyme-Linked et al.) test and the HI (Hemagglutination Inhibition) test are some of the laboratory tests used in determining immunity against yellow fever. The ELISA test is used to detect antibodies to the virus, while the HI test identifies neutralizing antibodies present in the ser |
|||
| um. Both of these tests are necessary for diagnosing yellow fever as well as establishing whether an individual has been vaccinated against this virus (World Health Organization, 2023). | |||
| Reporting agencies (Centers for Disease Control and Prevention (CDC)/World Health Organization (WHO)) | |||
Both the CDC and WHO provide information about instances of yellow fever. Yellow fever can cause severe illness and death, as well as spread rapidly, so both organizations provide information on it. They report cases of yellow fever to detect outbreaks and inform about ongoing preventive measures and treatment strategies.
Recommendations to decrease its prevalence
Some of the strategies to lower yellow fever rates include immunization, vector control, and personal protection practices such as using mosquito repellent and wearing protective clothes. For instance, vaccination is the most effective way of preventing the spread of
yellow fever (Arias, 2010). It is recommended that all travelers to endemic areas or people living in these areas be vaccinated. Additionally, eliminating any potential breeding sites for mosquitoes can help in minimizing transmission risks (Arias, 2010). Hence, it would be prudent for individuals to use insect sprays and put on protective clothing since this reduces the likelihood of mosquito biting. Furthermore, regular hand washing and avoiding contact with sick people are good ways to protect oneself from getting infected.
Accordingly, the WHO recommends that countries with endemic yellow fever should also strengthen their surveillance systems, maintain existing immunization activities, and enforce vector control programs. Moreover, the WHO further says that people traveling in regions where there is a high prevalence of yea low fever must vaccinate themselves while supplementing this with individual preventive measures in order to minimize the chances of contracting the disease.
Yellow fever is a severe and potentially deadly infectious illness. Vaccination is the most efficient method to prevent the virus from spreading, although vector management and personal precautions can lower the chances of transmission. Countries must maintain current immunization programs, and tourists to areas with high disease prevalence should be immunized and follow personal preventive measures to lower their chances of getting infected.
References
Arias, K. M. (2010). Outbreak investigation, prevention, and control in health care settings (2nd ed.). Sudbury, MA: Jones and Bartlett.
Emerging Infectious Diseases. (n.d.). Retrieved from https://www.cdc.gov/ncezid/diseases/emerging-infectious-diseases/default.html
Nelson, R. L., & Williams, C. H. (2014). Infectious Disease Epidemiology (3rd ed.). Burlington, MA: Jones & Bartlett Learning.
World Health Organization. (2023). fever. Retrieved from https://www.who.int/news-room/fact-sheets/detail/yellow-fever