WE live in an increasingly interconnected world. Travel from one continent to another is quicker than ever before. That ease of travel has also multiplied the risk of the spread of diseases which could otherwise have been contained locally.
The emerging cases of the Zika virus — which has caused babies to be born with abnormally small heads — outside Latin America are essentially a depiction of Steven Soderbergh’s Contagion. The human-mosquito-human transmission is increasingly being feared. The disease’s emerging in Pakistan via human vectors can only be a matter of time. Is Pakistan equipped to deal with the virus?
Zika is transmitted by the Aedes Aegypti mosquito that also carries the dengue, yellow fever and chikungunya viruses. A dengue outbreak in 2010-2011 in Pakistan infected thousands of people and claimed hundreds of lives. Medical teams from countries such as Sri Lanka and Indonesia came to assist the medical authorities here. WHO provided support for monitoring the infection. Experts assert that warm weather, lack of proper sanitation and overcrowding were possible reasons for the outbreak. They fear the same conditions might be behind the possible emergence of a more virulent strain of the Zika virus.
There are a few institutions such as Aga Khan University, that have the requisite expertise and collaboration eg with Centres for Disease Control, to anticipate and contain such an infectious threat. From the rest, not much can be expected. For a disease to be caught early, a detailed history, including of travel, is of importance. Unfortunately, doctors’ notes remain incomplete in most tertiary care centres in Pakistan.
Is Pakistan equipped to deal with the Zika virus?
Furthermore, people rarely come to the clinic for the mild flu-like symptoms that Zika can cause. And if an infected but asymptomatic patient were to mix with the general population, a disease outbreak would become hard to prevent or contain. A case in point is Brazil which has been hit the hardest amongst the Latin American countries. Almost 4,000 cases of microcephaly have already been reported there.
More alarmingly, Pakistan is a breeding ground for mosquitoes, and birth rates in the country remain quite high. Taken together this is a disaster waiting to happen. Even though no causal link has been confirmed yet, the strong association with the emergence of infection and a rise in microcephaly cases is suggestive of one.
The virus is also linked to the Gullian-Barré syndrome whereby peripheral nerves get damaged. Many infectious disease experts have already warned of this damage that might not be apparent until years after birth.
In fact, some countries in Latin America eg El Salvador have already advised women against getting pregnant until 2018. The virus has no known cure. The only advice experts can dispense is to use mosquito repellents and avoid getting pregnant because a vaccine may not become available for years. Two leading drug companies are already exploring their existing vaccine technology platforms to see if they can be applied to Zika.
The virus derives its name from the Zika forest of Uganda where it was first isolated from rhesus monkeys in 1947. The virus appears to attack the foetal nervous system where it impairs brain development leading to microcephaly, thus causing severe mental retardation. Almost 80pc of infected adults are symptom-free. In the rest, there is a mild rash, joint pain and/or conjunctivitis. Whereas blood tests are carried out on symptomatic patients those who are symptom-free and pregnant are advised an ultrasound to look for signs of infection in the foetal brain.
In the light of these facts, it would be a good idea for Pakistan to issue a travel advisory aimed especially at pregnant women and couples warning them against travel to the affected countries. People arriving from high-risk areas should first undergo thorough screening to rule out infection. As a general preventative measure, mosquito repellents such as DEET, picardin, oil of lemon, eucalyptus etc should be used. A sanitisation campaign to eliminate mosquito breeding grounds should be commenced immediately.
Screening is necessary for all couples who plan to have a baby, and for women who are already pregnant. In the latter category, those testing positive through ultrasound must receive counselling, and options for terminating the pregnancy should be discussed. Adults who are infected by the virus should prevent it from spreading by wearing protective clothing such as long sleeves and applying mosquito repellent.
In areas with heavy mosquito infestation, people should wear clothing treated with permethrin and sleep under bed nets. And in case of symptoms such as joint pain, fever, or redness of eyes, they must visit a clinic.
Kashif Majeed is an Aga Khan University alumnus interested in the study of the brain.
HR Ahmad is a professor of physiology at the Aga Khan University.
Published in Dawn, January 28th, 2016