Wednesday, 10 February 2016

Why Africa can’t afford to have an outbreak of the Zika virus By Adamson S. Muula


Group Leader, Dr Masafumi Inoue of Agency for Science Technology and Research's (A*STAR) Experimental Therapeutics Centre shows a sample to be tested with the Zika virus diagnostic test kit at their laboratory in Singapore, February 10, 2016. A*STAR and Singapore's Tan Tock Seng Hospital are collaborating to equip an existing diagnostic test kit with the capability to detect the Zika virus. If preliminary results are successful, the kits could be distributed to hospitals by the end of March in preparation for any outbreaks in Singapore. according to local media. File photo
Image by:  REUTERS
 
 
 Zika fever is a mosquito-borne viral disease caused by the Zika virus which is suspected of leading to the birth of deformed babies. The virus is transmitted to humans when an infected Aedes mosquito stings a person. Direct human to human transmission through sexhas also been reported.
The virus has spread to 23 countries in the South American region. Brazil has been the hardest hit with over 3700. Although the outbreak in Brazil has received the most attention, the virus has also since spread beyond the region to the Cape Verde Islands, which are off the coast of Senegal but are not part of the African mainland, Samoa and Tonga.


There are global attempts underway to stop the spread of the virus. It has been declared an international emergency by the World Health Organisation and the US’s Centre for Disease Control has put out six travel alerts so far.
There are several reasons Africa is least prepared to deal with an outbreak of the Zika virus. This includes the limited laboratory capacity and a lack of experts and funding.

Limited lab capacity

Firstly, the laboratory capacity to test for the virus is limited. Although the clinical features of the Zika virus are known, these are non-specific. This means other known diseases, such as malaria, have some - though of course not all - of the same signs and symptoms.
That Zika may appear like several other diseases makes laboratory testing for the virus imperative. But there are no widely available tests. This is unlike diseases or infections such as malaria and HIV/AIDS that have clinically tested and approved commercial laboratory tests or reagents.

Although inferior laboratories are not unique to Africa, in high income countries this challenge is mitigated by sending the tests to a national laboratory. For example in the US samples obtained from suspected Zika cases are now being sent to the Centre for Disease Control. In the UK the agency responsible is Public Health England’s Rare and Imported Pathogens Laboratory RIPL.
Although South Africa has the National Institute for Communicable Diseases, which could manage these tests in a standardised manner, several other countries do not have this capacity. Examples of the few comparable laboratories outside of South Africa are the Uganda Virus Research Institute and the Centre of Excellence for Genomics of Infectious Diseases at Redeemers University in Nigeria. But much of the continent does not have the infrastructural and human capacity to diagnose Zika.

A lack of experts

Facilities are not the only challenge. There is also a lack of proactive national and regional health experts to guide the response in case of any outbreak. This is a gap that needs urgent attention, not only for the Zika virus but also to deal with emerging and re-emerging infections.
There is much to learn from the Ebola epidemic which swept through several countries in West Africa in 2014 and 2015.

To effectively deal with the Ebola outbreak, international cooperation and collaboration was vital. Affected national governments, neighbouring nations and both local and international funders all came together to stem the spread of disease. For instance, Uganda and South Africa sent several teams of health workers to Liberia and Sierra Leone. There was significant capacity building which would not have taken place had this manpower not been available.
The international collaboration continues in terms of searching for a vaccine as well as the treatment and care of Ebola patients. We have learned that fragile health systems are more susceptible to infectious diseases epidemics.

Another challenge which the Ebola outbreak should teach Africa is that in terms of a disease spreading, no country is an island. While there may not be local transmission of Zika in a particular country, there is no guarantee that a country will not have individuals who travel to or come into it carrying the disease.
Unlike Ebola where direct human to human transmission through droplets was a concern, it is note that easy to transmit the Zika infection. The Aedes mosquito is needed as an intermediary or sexual intercourse must occur between an infected person and a susceptible individual. Therefore the border control needs for Ebola are more stringent than Zika. A Zika infected individual who travels from one country is more at individual risk of not being diagnosed and receiving appropriate care than of transmitting the infection.

No unified body

Unlike in the US, there is not a unified body of health experts on the continent. The available regional bodies such as the West African College of Physicians and the soon to be launched College of Physicians of East, Central and Southern Africa have their jobs cut out already to lead in the health sector.
The World Health Organisation’s African Regional Office, unlike its Pan American Health Organisation (PAHO), does not proclaim advisories and guidelines apart from those decided at headquarters in Geneva.

As early as July 2013, the African Union Summit identified the need for an African centre for disease control modelled on the on the in the US. Among its responsibilities would be surveillance and response, which would include an emergency operations centre. Although the centre has been launched, it has yet to handle its first epidemic. Until the African centre for disease control is fully active, there is no comparable entity for Africa.

The re-emergence of diseases such as Zika calls for African states and experts, as well as the international community, to join forces to build the continent’s disease response capacities.

Adamson S. Muula: Professor of Epidemiology and Public Health, University of Malawi

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