Zika Virus In Angola: Tracking The Cases

The Zika virus, first discovered in Uganda in 1947, has spread to over 60 countries and territories since an outbreak in Brazil in 2015. Angola, a major travel hub in Africa, reported its first two cases of the Zika virus in 2017. Since then, the country has seen a rise in cases of microcephaly, a rare birth defect marked by a small head and serious developmental issues. Between February 2017 and May 2018, there were at least 72 reported cases of microcephaly in Angola, suspected to be linked to an emerging Zika outbreak. While the exact number of Zika cases in Angola is unclear, the presence of the virus and its potential for transmission throughout the continent has raised concerns among experts.

Angola's first two cases of Zika were reported in 2017

Angola's first two cases of the Zika virus were reported in 2017, marking a concerning development in the global spread of the disease. The cases were detected in Luanda, the country's capital and a major travel hub in Africa, raising concerns about the potential for further transmission throughout the continent. The World Health Organization (WHO) had declared Zika a global public health emergency in 2016 due to its link to birth defects, particularly microcephaly, and its rapid spread through the Americas.

The first two cases in Angola included a French tourist, who has since left the country, and an Angolan resident, who was hospitalised after being diagnosed. These initial cases were reported just three months after Angola controlled a yellow fever epidemic that killed at least 400 people. The country's health minister, José Luis Gomes Sambo, emphasised the need for preventative measures, especially vector control to combat the mosquitoes that transmit Zika.

The detection of Zika in Angola is significant due to the country's role as a gateway between Africa and South America, with substantial air travel connectivity. The virus strain in Angola has not yet been determined, but the presence of the Asian genotype, which has been linked to severe outbreaks and birth defects in Latin America, would be particularly concerning. The limited diagnostic and surveillance infrastructure in Angola and other African countries poses challenges for tracking and containing the outbreak.

The Zika outbreak in Angola has largely gone unreported, but an internal WHO report from April 2017 concluded that the two cases confirmed earlier that year, along with subsequent microcephaly cases, provided "strong evidence" of a Zika-linked microcephaly cluster in the country. Angola's health system faces challenges, including a lack of data, diagnostic testing, and adequate resources, making it difficult to track and manage the outbreak effectively.

The Zika virus was first identified in Brazil in 2015

In early 2015, health authorities in Brazil reported clusters of cases involving a rash in the state of Maranhao. Samples from these patients were tested, and while some cases were attributed to dengue, the presence of the Zika virus was not initially suspected or tested for. However, by late April 2015, authorities in the state of Bahia detected the Zika virus in samples, and this was later confirmed by the Evandro Chagas Institute, a national reference laboratory.

The first case of Zika in Brazil was confirmed in May 2015 in a 52-year-old man in the state of Sao Paulo. Soon after, the virus spread to multiple states, including Alagoas, Bahia, Maranhao, Para, Rio Grande do Norte, and Sao Paulo. By July 2015, authorities reported neurological complications associated with the rash illness, including cases of Guillain-Barré syndrome.

The Zika virus continued to spread across Brazil, and by November 2015, the country officially declared a National Public Health Emergency due to the increasing number of cases of microcephaly in the states of Pernambuco, Paraiba, and Rio Grande do Norte. This declaration highlighted the potential link between Zika and severe birth defects, drawing global attention to the emerging outbreak.

The World Health Organization (WHO) played a crucial role in the response to the Zika outbreak. In May 2015, they issued an Epidemiological Alert to raise awareness among member states and provide recommendations for surveillance and control measures. As the situation evolved, WHO continued to provide updates and guidance, eventually declaring a Public Health Emergency of International Concern in February 2016.

The emergence of Zika in Brazil sparked concern among health experts worldwide. The virus had previously circulated quietly in Africa and Asia, causing mild symptoms, but the Brazilian outbreak raised alarms due to its association with microcephaly and other neurological disorders. This development underscored the need for enhanced surveillance, research, and public health measures to address the growing threat posed by the Zika virus.

The Asian strain of Zika has been linked to microcephaly

The Asian strain of the Zika virus has been linked to thousands of cases of microcephaly. The virus was first discovered in Uganda's Zika forest in 1947 and circulated quietly for years, causing mild, flu-like symptoms in parts of Africa and Asia. Over time, the virus diverged into two genetically distinct lineages: the African and Asian strains, neither of which was initially associated with large epidemics.

In late 2007, the Asian strain caused the first significant Zika outbreak on the island of Yap in Micronesia, infecting 73% of residents over the age of three. However, it was not until an outbreak in French Polynesia in 2013 that the virus was first linked to microcephaly.

The Asian strain of Zika was then detected in Brazil in 2015, and by 2016, it had spread to nearly all the states in the country, with thousands of babies born with small, misshapen heads as a result. This outbreak led the World Health Organization (WHO) to declare a global public health emergency in February 2016. Since then, the Asian strain has caused serious outbreaks in other Latin American countries as well.

In 2017, an unusual rise in microcephaly cases in Angola raised concerns about a potential Zika outbreak on the African continent. An international research group, including experts from Oxford University and Angola's health ministry, investigated and confirmed that the Asian Zika strain was responsible for the increase in birth defects. This was the first time the Asian strain had been linked to microcephaly in an African country. The team conducted molecular testing, genome sequencing, and an epidemiologic investigation, revealing that the Asian Zika genotype had been circulating in Angola since at least 2016 and was likely introduced from Brazil due to the high volume of travel between the two countries.

The findings highlighted the need for increased surveillance in areas with high travel connectivity to regions where Zika and other mosquito-borne viruses circulate. Experts worry about the potential spread of the Asian Zika strain to other African countries and the lack of adequate surveillance and health infrastructure in many at-risk African settings.

Angola's inadequate health system makes tracking the outbreak difficult

Angola's inadequate health system, along with a lack of data and diagnostic testing, has made tracking the Zika outbreak difficult. The country's public healthcare system is characterised by low standards, limited access, insufficient funding and staffing, and outdated medical technology and infrastructure. Treatment at state hospitals and clinics is provided free of charge, but the quality falls short of the standards that many expatriates are accustomed to. The majority of the population faces significant challenges in accessing medical care.

The World Health Organization (WHO) has identified at least 72 babies born with microcephaly in Angola between February 2017 and May 2018, suspected to be linked to the emerging Zika outbreak. These cases have largely gone unreported, and the actual extent of the outbreak remains unclear due to the deficiencies in the Angolan health system. The internal WHO report underscores the urgency of strengthening surveillance and control measures in the country.

Angola's health system faces considerable challenges, including a shortage of trained medical professionals and outdated equipment. The country's best hospitals are concentrated in the capital city of Luanda, but even these facilities often fail to meet international standards. The language barrier also poses a significant challenge, as most medical staff in Angola speak Portuguese, with some Spanish-speaking doctors also available due to the presence of Cuban medical professionals. However, English-speaking doctors are scarce, which can create communication barriers for expatriates and locals who do not speak Portuguese or Spanish.

The inadequate health system in Angola has direct implications for the management of the Zika outbreak. There is a lack of testing capacity, which means that many cases of microcephaly and Zika infections likely go undetected or unconfirmed. This situation is further exacerbated by the limited access to advanced testing technologies, particularly in rural and remote areas. The outbreak has occurred at a time when global attention and funding for Zika have waned, and the Angolan government's focus on other pressing health issues, such as malaria, cholera, and the potential threat of Ebola, further complicates the response to the Zika outbreak.

The consequences of the inadequate health system are far-reaching. Families affected by Zika-related birth defects face significant financial and logistical challenges in accessing necessary care. They are often referred to the Center for Neurosurgery and Treatment for Hydrocephaly in Luanda, which suffers from inadequate funding and places a financial burden on families who need to pay for consultations. The lack of a comprehensive public health programme to support children with Zika-related birth defects further exacerbates the challenges faced by these families.

The Zika virus is spread by mosquitoes

The Zika virus is primarily transmitted by the bite of infected mosquitoes, specifically the Aedes aegypti and Aedes albopictus species. These mosquitoes are prevalent throughout the Americas and typically bite during the day and early evening. They are also known to carry other viruses such as dengue, chikungunya, and yellow fever.

The risk of contracting the Zika virus is particularly high for pregnant women and their fetuses. If a pregnant woman is bitten by an infected mosquito, the virus can cross the placenta and infect the fetus, potentially leading to serious birth defects such as microcephaly, a condition characterised by a small head and serious developmental issues. The Zika virus has also been linked to other congenital malformations, preterm birth, and miscarriage.

In addition to mosquito bites, the Zika virus can be transmitted through sexual contact, blood transfusion, laboratory exposure, and possibly organ transplantation. However, mosquito-borne transmission remains the primary mode of infection.

To prevent the spread of the Zika virus, it is crucial to protect against mosquito bites, especially for pregnant women and those planning to become pregnant. This can be achieved by wearing long-sleeved shirts and long pants, using insect repellent, and sleeping under mosquito nets. It is also important to eliminate mosquito breeding sites, such as standing water and trash, to reduce the mosquito population.

While most people infected with the Zika virus do not exhibit any symptoms, some may experience mild flu-like symptoms, including rash, fever, conjunctivitis, muscle and joint pain, malaise, and headache. These symptoms typically last for 2-7 days and rarely require hospitalisation. However, the impact of the virus on pregnant women and their fetuses can be significant, underscoring the importance of mosquito-borne transmission prevention.

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