Public Health Dept. fortifies battle against deadly dengue

Saturday, 19 July 2014 00:36 - - {{hitsCtrl.values.hits}}

Completes inspecting 117,000 houses this month
Identifies temporary breeding sources
Orders residents to clear the temporary breeding sources in their premises
Takes legal action against those responsible for permanent large breeding places
Adopts ‘active surveillance’ for first time in Sri Lanka and ‘high risk strategy’
Embarks on ‘zero dengue death drive’

Public Health Department Chief Medical Officer of Health Dr. Ruwan Wijayamuni

The Colombo Municipal Council had launched a dengue eradication campaign earlier this year, as they predicted a large outbreak of dengue in the month of May and the months following, given the intermittent showers being experienced at the time. Judging from the dengue cases in April they had found that there were more patients during that month than in March and an upward trend was thereby noted. Calling for immediate action in response to the warning signs that were appearing following the showers, they embarked on the campaign. This month, with dengue cases and deaths still prevailing after the launch of the campaign and after various other initiatives have been taken by the relevant authorities, it is evident that the deadly epidemic has not been contained. In an interview with Public Health Department Chief Medical Officer of Health Dr. Ruwan Wijayamuni, Weekend FT enquired into the present situation in terms of how serious it is, whether numbers have reduced, what they have been doing so far to eradicate the disease, what has been the outcome of their efforts and what they plan to do next. “Numbers are coming down,” said Dr. Wijayamuni. “Usually when we look at the data and statistics, each year we have two peaks in relation to dengue – soon after the monsoonal rains and during the monsoonal rains – that is June/July and November/December,” he explained. “In the first two weeks of the month of June 2013 we had a 60% increase in cases. With all the actions that we have taken to curb dengue, by the end of June this year we were able to bring the numbers down to a 40% increase. The entire country experienced the increase – not just Colombo. Compared to last year, our numbers are less. Dengue is not a problem just in Sri Lanka; other countries are also facing this problem what with global warming, El Nino etc.” Climate change due to global warming can change the geographical range of vector mosquitoes, extend the disease transmission season and reduce the time taken for ingested viruses to develop to infective stages in mosquitoes. Vector-borne diseases account for 17% of the estimated global burden of all infectious diseases. Dengue is now the world’s fastest growing vector-borne disease with a 30-fold increase in disease incidence over the past 50 years. Outbreaks of dengue fever have been reported from all countries in WHO’s South East Asia region, Dr. Wijayamuni said. There have been a number of countries consistently reporting dengue to the WHO over the years and Sri Lanka is among them. Dengue infections have been endemic in Sri Lanka and these countries since the mid-1960s and dengue fever (DF)/dengue hemorrhagic fever (DHF) epidemics are experienced by the country for over two decades, he noted (refer diagram). In 2002, DF/DHF was ranked as the third most common notifiable disease in Sri Lanka (first and second were malaria and tuberculosis), he added.

What have we done about this?

“What have we done about this and what have we done differently? I strongly believe that all this time the city of Colombo was trying to be an isolated geographical area when it comes to dengue and other things but I do not believe in that because it’s a global village now. We can’t be isolated from the rest of the country or the rest of the world. So I made an appeal to the Ministry of Health to lend a helping hand, especially in terms of manpower,” he said. “Then the Presidential Task Force was there and the President also instructed the three forces including the police to have a program to curtail the dengue menace within the country. We embarked on a program during 20, 21 and 23 June; I selected 21 high risk wards and we went house to house – we were able to inspect 53,533 households. “In around 1.7% of houses, we found breeding places. That’s a large number. Nevertheless, though we don’t find many temporary breeding places like yoghurt cups, we’ve found large, most probably permanent breeding grounds, for example, tanks and roof tops and improperly built bathrooms where the water remains for a long period. It’s the ideal breeding ground for Aedes and a lot of people have not paid attention to this. We have ordered them to provide means of draining out the water by creating a slope and we have taken legal action against them.” That was the first phase of their control program. They commenced the second phase on the third of this month. On 3 and 4 July they completed the Colombo North and Central Colombo ‘A’ area and were able to complete visiting 38,832 houses; they found 125 breeding places against which they will be taking legal action. Then again on the 5th they had a cleaning up campaign from Dematagoda to Fort and on the 8th and 9th they had an inspection campaign. The 10th was the last day, when they targeted Colombo East and West. “Once we finish all that, we would have finished all 117,000 households in the Colombo City limits. This has happened for the first time in history – we have never ever done that! We are working tirelessly. In the first phase we spent three days, second phase we spent six days – in nine days we have used 2,000 troops and officials each day, that’s 18,000 people that we have deployed – this is a massive operation!” he exclaimed. What we’ve been doing during these nine days is: inspection, identification of temporary breeding grounds and getting the residents to destroy them. “As for permanent breeding grounds, we have taken legal action. This is the only way out that we can think of because there is no medicine, there is no vaccine,” he said.

Identifying dengue prone areas

He also highlighted issues that he came across when identifying dengue prone areas and plotting data showing the number of cases against wards. “There are 47 municipal wards but when I was plotting the data to establish the number of cases against wards I found that not all 47 wards are giving dengue cases; there are only 21 municipal wards that are producing a large number of cases. Mattakuliya, Mahawatte and Lunu Pokuna are giving a very high number of cases as are Kuppiawatte, Borella, Kirulapone, Bambalapitiya and Havelock Town. I recognised these wards as high risk wards.”

High-risk strategy: The eye-opener

“These 21 wards are the real producers of dengue cases. So I considered them; no one has done this before and when I plotted this, it was an eye-opener for everyone. This was when we adopted the high-risk strategies. There are two strategies that we can apply when concluding dengue. One is the community strategy and the other is the high-risk strategy,” he explained. Here they have adopted the high-risk strategy which means they selected the high-risk wards or the geographical areas that are producing the highest number of cases. Then they conducted a comprehensive dengue control program within those high-risk areas so that they can focus; they can put their resources more efficiently, rather than going for a blanket cover – trying to do everything little by little in each and every area. “We focussed our attention, resources, materials, chemicals and money into those high risk areas,” he said, pleased with their effective and practical use of men, material and money!

Active surveillance

Another approach they have adopted is the means of collecting information regarding dengue incidences, which has proven to be very effective. “My people go to the hospitals and collect the data without waiting for it to be reported to the epidemiological unit and then reported to us as this takes about two weeks. When they are admitted, our fellows go and catch the data and we adopt. This was established by me. This is called ‘active surveillance,’ conducted for the first time in Sri Lanka!” he declared with pride.

Zero dengue death drive

“We have embarked on something called a ‘zero dengue death drive’ for Colombo, where I’m trying to minimise; I’m trying to bring the dengue deaths down to meet the absolute minimum; near zero. If one gets the disease, is disabled for a few days but does not die, then fine – match over. But last year we had 13 deaths, in 2011 we had 29. So far we have six deaths this year; after the last one reported in March there was unfortunately another one reported four weeks ago, where a 29-year-old seven-month pregnant woman from Maligawatte died. “When we inspected her premises, they were extremely clean and so were her surroundings but unfortunately 10 metres away was the railway track!” Dr. Wijeyamuni said, referring to the railway track in the Maligawatte area which has been notorious for its appalling conditions in terms of hygiene. That triggered him to take action with regards to the railway track and realising that just prosecuting the station masters won’t do anything, he decided they should get physically involved and do something tangible so that they can bring down the number of cases.

Maligawatte railway track clean-up

Identifying Maligawatte West as an area with high incidences, they had a program in the railway track on Saturday, 5 July. “We cleaned up the entire muck that has been thrown out by commuters – containers, yoghurt cups, ice-cream cups and empty bottles onto the railway tracks. There were six tractor loads of rubbish of all sorts that were cleared along the tracks from Fort to Dematagoda. “We deployed 750 people, one team from Fort, two teams from Maradana and one team from Dematagoda. The Dematagoda team started from Dematagoda and came up to Maradana; from Maradana two teams, one team going towards Fort and one towards Dematagoda. This is all across the railway line. We parked six tractors along the road and we were able to collect all this muck,” he explained.

Change our attitudes

Referring to his chart displaying the occurrences of dengue cases in the various municipal wards, Dr. Wijayamuni pointed out, “As you can see from the chart, Maligawatte West is a culprit. It has always been making trouble. It has always given more numbers of cases. It always peaks each year in June and July. So in this case the railway track could’ve been the source.” The starting point of the problem was basically negligence on the part of the commuters – their lack of responsibility by throwing their rubbish onto the railway tracks and letting them accumulate has caused so much trouble. “These are the things that we have to really get into the minds of the people because people have the knowledge; they have enough information; the information has transcended into knowledge but we have failed to change their attitude. The knowledge is there. They know where the dengue mosquitoes are, at what time they are biting but unfortunately people still do throw things; they discard just like that. “We have a problem as a nation and if we don’t change our attitudes and inculcate good practices, healthy practices, we are done!” he observed. Be vigilant In many instances, even with the individual or some groups keeping their own surroundings clean, they are still at risk of contracting dengue due to the negligence of other members of the community. In such situations it is important for them to be vigilant. When asked what the general public can do to protect themselves from the disease, Dr. Wijayamuni said there are a few things that we can do. Firstly for dengue to spread, the ‘reservoir’ is the dengue patient and there should be another person who is susceptible to contract the disease. This virus has to go out of the patient’s body and enter the healthy person. The mosquito is only the vector which is doing that part. So what we are mainly doing is we are controlling the vector but we also have to concentrate on the reservoir. During the fever, which is when the ‘viraemia’ (that means the virus inside the dengue patient) is taking place, if a mosquito is taking a blood meal, with that blood the virus goes into the mosquito’s body. Then the mosquito injects it into the healthy person. This is how it’s being spread. “I have issued a circular to all the hospitals within the city of Colombo, stating that with any fever patient – the cause may be anything – they have to keep him under a mosquito net so that the mosquito will not have access to him. At home also we have to do the same thing especially during this dengue period. And of course we have to protect the host: apply any repellent, wear long sleeves, long pants and minimise the mosquito-man contact. If you can do that we have done our job,” Dr. Wijayamuni concluded.

Dengue’s adverse impact on tourism

Scores of tourists are attracted to Sri Lanka during the summer vacations and the winter vacations. The June-July peak and November-December peak, which is the time when the numbers of dengue cases go up, unfortunately coincide with the vacation patterns both locally as well as internationally. In 2013 alone, Sri Lanka recorded 31,861 cases of dengue which were reported to the Health Ministry’s Epidemiology Unit from across the island. Approximately 51% of these cases were reported from the Western Province. Interestingly, the highest number of dengue cases was reported during the month of January, which coincides with the peak winter tourism season. As a result, the national health services of foreign countries such as Australia, Canada, US and UK have begun to issue health advisories to travel to Sri Lanka. “This is a worrying trend given that the country has battled travel advisories on the grounds of terrorism in the past,” Dr. Wijayamuni said. “Having to battle travel advisories based on a possible risk to health and the classification of dengue epidemics and pandemics, could throw the local tourism industry into disarray once again,” he added. While the country aims to raise tourist arrivals to 2.5 million by 2016 and targets tourism revenues to garner the No. 1 rank in foreign earnings, the threat of having a reputation as a dengue infested destination will put a dent in Sri Lanka’s strategic tourism objectives. Therefore, not only is the economic burden of the disease growing exponentially, dengue is also posing a potent threat to tourism, he stated.