‘2016 may turn out to be the year of Zika’

2016 and beyond need not be the years of Zika if all the stakeholders at risk and in at-risk areas play the game well

The Zika virus, that is. The title is in fact the concluding line of one article among the many that are being published since the Zika threat went public in Brazil recently, and following the declaration by WHO of the zika virus being declared a public health emergency. This step was taken after an emergency meeting in Geneva to discuss the ‘explosive’ nature of the virus.

It will be recalled that this is the fourth time that WHO has declared a state of emergency. The first was in 2009 for the AH1N1 virus. The second and third were in 2014 for outbreaks of polio and Ebola, the latter in Sierra Leone where it had been responsible for an estimated 11000 deaths.

WHO was heavily criticized for what was deemed a delay in declaring Ebola as a public health emergency. ‘Damned if you do, damned if you don’t’ seems to be the unfortunate fate of WHO. Thus, in the case of the AH1NI virus, it was criticised for being too hasty in declaring a global pandemic, on the grounds that there was insufficient evidence at the time, and also that there was some vested pharmaceutical interest in doing so. This claim was subsequently overturned by a high level investigative committee in its report.

The point that is missed in these criticisms is that decisions can only be taken on the basis of available scientific evidence at the given time, and that such evidence is probabilistic in nature because of the number of variables involved, many of which are unknown especially when it comes to living organisms which are infinitely complex.

As a leader in the special issue (19/26 December 2015) of New Scientist puts it under the title ‘Uncertainty principles’, ‘The world is full of complexity and confusion. …Science while it can only deliver probabilistic and partial answers, helps us…to reduce the uncertainties of a world continually reshaped by nature and technology.’

But WHO declaring a public health emergency, after factoring in all the known variables for a start, helps to trigger ‘increased money and efforts to stop the outbreak, as well as prompting research into possible treatments and vaccines’. The concern is not so much the virus per se as the cluster of cases of the birth defect known as microcephaly (small head) and its suspected link to the Zika virus.

Further, one must not forget that such a decision has serious economic and social implications, which WHO is fully aware of, and that is why for the time being it has ‘found no public health justification for restrictions on travel or trade to prevent the threat of Zika virus.’

Thus, the Brazil carnival is on and hundreds of visitors and tourists have already started streaming in. Similarly, the scheduled World Cup in Brazil is not going to be cancelled.

Zika and its spread

Zika was discovered in macaque monkeys in 1947 in Uganda’s Zika forest. It was nearly a decade later that the first human case was detected, spread by the mosquito Aedes egypti. It causes a relatively mild and short-lived infection, symptoms consisting of a brief high fever, a rash, red eyes, some joint pain and in the worst cases a bit of headache and nausea, ‘barely worse than a dose of flu’.

But what is worrying is that the virus has been spreading beyond Central Africa, and more so since 2007 when there was an outbreak of 180 cases in the Micronesian island of Yap in the Pacific Ocean some 1,800 km east of the Philippines. In 2013, a massive outbreak occurred in Polynesia, in the eastern end of the Pacific Ocean. It has since spread to Brazil, and according to WHO to several other countries in South America, including Mexico.

It is feared that it is only a matter of time now before it travels north to the US and Europe. According to the US Centres for Disease Control and Prevention (CDC), Zika transmission is ongoing in Brazil, Columbia, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Surinam and Venezuela.

Zika and microcephaly

Microcephaly means that the head does not grow to normal size in the foetus and thus the baby is born with a small head, and there is the possibility of brain damage as a result.

Although there is no definite proof as yet of a causal relationship between the Zika virus and microcephaly – that is, exactly how does Zika produce this disorder? – the fact that Brazil has experienced an explosive growth in cases of microcephaly and Zika transmission is a matter for concern in the medical community.

Normally, the country reports about 200 microcephaly births a year, but since last October, Brazil has seen nearly 4,000 reported cases of newborns with microcephaly, mostly concentrated in the poorer region of Pernambuco in the north east where between 1 and 2 per cent of newborns now have microcephaly – the normal rate is about 0.07 per cent. At about the same time, the Zika virus has spread rapidly throughout Brazil.

But scientists also saw an increase in microcephaly in Micronesia in 2007 and French Polynesia in 2013-14 where many foetuses with microcephaly had been aborted. Other evidence suggests a link, such as two-thirds of mothers with microcephaly babies saying they had a rash during pregnancy, and the recovery of Zika virus in the womb and in still-born babies.

There is therefore a lot of work to be done to establish the causal link: nevertheless, the evidence at hand is sufficiently strong to put us all on alert, and to assist the authorities in the efforts to prevent spread.

Issues related to Zika

There are medical and public health issues.

On the medical front comes the question of whether to terminate the pregnancy of pregnant women who are affected by the virus, a very thorny issue in Brazil with strict anti-abortion laws. There is also the problem that microcephaly can only be detected late in pregnancy, when termination may not only be technically complicated but also raises ethical issues since the foetus is viable.

On the other hand, there are anecdotes such as that of a 23-year old woman who was diagnosed with microcephaly at birth, and she explained to a reporter how doctors had given her only a few years to live, during which she would suffer from various physical and mental disabilities, and be both a health and social burden on her parents. But she went on to live a normal life, graduated from university and is working. One can see the human dilemma that this poses to doctors who have to shoulder the responsibility of whether or not to advise termination of pregnancy.

Next is long-term prevention: development of a vaccine against Zika. This is going to be a long haul, more than ten years, not least because of the scientific aspects involved, but also because of the ethical problems that will arise for planning trials in pregnant women.

Prevention is still better than cure

Given these constraints and realities, pregnant women have been advised to avoid travelling to countries where Zika is known to exist. For those who do intend to travel, they are strongly advised to minimise the risk of mosquito bites, both at night and during the day. They should use insect repellent and wear long-sleeves and other clothing that minimises skin exposure. Women living in these countries are being advised to postpone pregnancy if they can until more is known, and those who are pregnant to take all protective and preventive measures against mosquitoes.

Postponing pregnancy is part of the personal responsibility expected of people, along with putting in practice all the other measures recommended, such as the ones mentioned above. These must complement the general ones such as meticulously clearing all breeding places in one’s living environment starting with the house, where empty cans or other containers must be disposed of, and stagnant pools of water eliminated. This is not a one-off affair: it must be a regular routine to check these danger spots and get rid of them. In parallel, governments must match these initiatives by keeping citizens informed, spraying the appropriate insecticides, and drain the swamps and other such areas where mosquitoes breed. ‘Such methods worked in the past, and can work again today.’

Scientific endeavour at the global level supported by political will, and responsible citizens complementing government efforts can no doubt lead a successful battle against Zika. 2016 and beyond need not be the years of Zika if all the stakeholders at risk and in at-risk areas play the game well.

RN Gopee

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