Curbing dengue

ONCE again, the dengue outbreak is making headlines. Data recently released by the National Institute of Health (NIH) has shown the extent of the current outbreak. From the samples collected from Rawalpindi and Islamabad, the NIH found Dengue Virus Type 2 to be the causative agent of the disease. In Rawalpindi, most dengue cases were reported from the Airport Housing Society, Gulbahar Scheme, Wakeel Colony, Dhoke Munshi, Dhoke Kala Khan and Kot Jabbi, while in Islamabad the cases were clustered in Mohra Nagial and UC Kirpa areas.

According to the NIH assessment, response measures have included better reporting and coordination between private and public hospitals and related government departments; an increase in bed capacity; the setting up of health camps and fumigation in dengue hotspots; and improving community awareness.

The prime minister's special assistant on health, Zafar Mirza, has also highlighted the gravity of the crisis. He said last month that over 14,000 cases had been reported from all over Pakistan. Since then, the numbers have risen and continue to rise, making it difficult to keep pace. According to some estimates, the figure for dengue cases has crossed 20,000, with the largest number emanating from the Potohar region.

Meanwhile, the responses to the outbreak must be improved further. They are broad and generic, and usually initiated after each episode of a dengue outbreak. Given the regularity of the outbreak of dengue in the country, the government's preparedness and response should have, by now, become more fine-tuned.

The first case of dengue in Pakistan was reported in 1994 from Karachi. From then onwards, dengue has been surfacing in different parts of the country each year with varying intensity - 2011 saw the worst outbreak in Lahore which claimed around 300 lives. Some lessons were learnt along the way, and political ownership of the response to the outbreak was cited as one of the major factors that enabled better control over the dengue virus. A robust surveillance system is missing.

However, this year, the overall response by provincial governments has been lackadaisical. The communication gap between different government departments has also contributed to the situation. This is so, despite the fact that all provincial governments were forewarned in May of an impending epidemic, as revealed by Dr Mirza. Let us hope that this intervention will help the authorities limit the further spread of dengue.

We are, once again, dealing with a dengue outbreak in the absence of an effective and extensive surveillance and intelligence system. Despite witnessing several countrywide outbreaks over many years, the disease surveillance system is still limited to only a few cities. The absence of a well-coordinated system has also played a part in delaying the early detection of dengue, thus resulting in the haphazard and ad-hoc response seen this year.

Even though the clustering of cases can be traced to specific areas in Rawalpindi and Islamabad - thanks to the good work of the NIH - epidemiologists want to locate active cases of dengue as well as prioritise the surveillance of vectors (disease carriers). An effective surveillance system would help the authorities have prior knowledge of the focal areas where dengue is likely to strike, enabling better preparation and a timely response.

In the age of globalisation and increased trade and travel, such outbreaks have acquired global dimensions with respect to health security and international health regulations. This is why a robust response system to disease outbreaks is also required to stave off any global repercussion of a local epidemic.

In terms of further preventive measures, community-oriented initiatives aimed at raising awareness and adoption of protective measures can lessen and contain future outbreaks. In this regard, the community dengue alert system in Singapore has shown promising results and can be emulated in Pakistan.

There are also new biological techniques being developed to stop the mosquito from breeding and transmitting the virus. One such technique involves releasing genetically modified mosquitoes into the vector population that interfered with the sexual cycle of the female disease-carrying mosquitoes, stalling further breeding. This technology has shown promise in trials conducted in Southeast Asian countries.

But the key to containing any outbreak is an effective and robust disease surveillance system. This includes better preparedness, early detection of cases, rigorous investigation and notification mechanisms backed up by well-equipped hospitals and coordinated workforces that is comprised of the political, administrative and community leadership.