Zika

A quick word on the Zika virus. The name "Zika" refers to a forest just outside Uganda's capital, Kampala, where the virus was discovered in the late 1940’s. It has since been identified in other parts of Africa, Southeast Asia and the Pacific islands. The spread of Zika is similar to that of the chikungunya virus: Once it is exposed to a dense population, aided by the right factors and conditions, it spreads rapidly. Concerns about severe birth defects associated with the Zika virus are not only understandable, but also are aggravated by the difficulty in detecting infection. Several studies are underway to conclusively prove the link between Zika and microcephaly, a congenital disorder associated with small infant head size and neurological impairment. Studies in Brazil have already shown a strong correlation. There is also evidence linking Zika to autoimmune disorders such as Guillain-Barre syndrome, but more findings will likely emerge over the coming months.

However, hard facts are difficult to come by and the media are not being proportionate in their reporting. It may well be proved to be very serious but the BBC colouring the whole of Brazil in crimson red on their graphics is hardly helpful. One recent report suggests that up to last week there were only 270 confirmed cases of microcephaly in Brazil and only 6 of those had Zika. 

There are also some suggestions amongst the Twitterati that there may be a story drawing in the mandatory Tdap vaccination for pregnant women in Brazil, (became mandatory in 2015). Tdap is manufactured by Glaxo and Sanofi. There also seems to be growing evidence that the disease can be sexually transmitted. I’m not taking a view on any of this. I’m simply keeping an open mind and question how a 65 year old virus suddenly becomes a threat to human health on a trans-continental scale. Mossies rarely travel far.

The WHO officially considers the Zika viral outbreak, which is currently plaguing the Americas, to be a global emergency. Yesterday’s announcement followed an extraordinary meeting to assess the extent of the infection. Labelling the virus an international health emergency improves the chances of getting it under control, thanks to an anticipated influx of personnel, resources and expertise spurred by the WHO designation. The emergency decision could even accelerate efforts to develop a vaccine, though this will not happen immediately. The virus is spreading rapidly through South and Central America and could lead to 4 million new cases this year. At least 20 territories, including Panama, Guatemala, Barbados and Puerto Rico, have registered local transmission of the virus. The disease, which is spread by the Aedes mosquito, produces no symptoms in the majority of cases and only mild symptoms in others. 

 There will be an economic impact. Containing and managing an outbreak is expensive, as is dealing with large numbers of dead and infected. This can lead to severe disruptions in trade, accompanied by enhanced screening measures to prevent the transmission of the virus across borders. Developing treatment, cures and vaccines requires huge investment, as seen in the recent Ebola outbreak in Africa. And then there is the loss of productivity resulting not only from sickness but those refusing to work and those taking time off to care for the infected. If the disease is neither deadly nor debilitating, however, the loss of economic productivity from death or incapacitation is low.

Mossies are a fact of life in the Tropics and whatever personal protective measures individuals take its usually a case of minimising bites rather than eradicating them. Zika is not the only mosquito-borne disease that is endemic to the Americas; dengue, chikungunya, West Nile and malaria have all taken hold, (before I was posted to Belize I came out of the Med Centre feeling like a pin cushion although at the time, the last thing we were worried about in the jungle and in the rivers were mossies. The Green Tree Viper, the Fer de lance, the Jumping Viper, the Bullet Ant, African Bees, bitey spiders too numerous to mention and scorpions; nice). Without mass eradication efforts, similar to those carried out in the mid-20th century, it is likely that several mosquito-borne diseases will remain endemic to Latin America. The difficulty in controlling these other diseases is a strong indicator that controlling Zika will be equally difficult. There are significant costs associated with constantly combating and treating mosquito-borne diseases, costs that are hard for cash-strapped countries to shoulder. In fact, the prevalence of such diseases in the tropics has historically hindered the economical emergence of countries in that climate range.

The biggest geopolitical effect of this outbreak may not be seen until 18 years or more after the current outbreak. Fear of Zika and microcephaly has to potential to lead to a decrease in pregnancies in the region, possibly assisted by political initiatives. The governments of El Salvador, Columbia, Jamaica and Honduras are already telling women to delay pregnancy until the virus is under control. Unlike other countries and regions that are expected to face demographic crunches in the next two decades, much of Latin America still has a healthy demographic curve, with a large, young population base. A rapid halt in population growth, caused by something akin to Zika, would threaten the continued productivity associated with sizable Latin American labour pools. This has the potential to hasten regional decline in decades to come although, I do emphasise, no one seems to yet have real handle on this thing regardless of what the newspapers are saying..