With deadly Covid-19 epidemic just receding although far from over, the last thing Pakistan needed was the outbreak of yet another potentially deadly disease. But the unfortunate rise of the dengue virus at this juncture is posing precisely that challenge.
Some 9,996 confirmed cases of dengue have so far been reported across in different cities of Punjab during the current year, 6,640 of them reported in Lahore alone. Many cases have been reported in Islamabad, and of late, in the Khyber-Pakhtunkhwa province.
The coronavirus is on the decline but it still exists and health experts maintain it will continue to exist in the coming years. The number of confirmed coronavirus cases is 1,269,234 while active cases are 23,940 in the country.
As far as dengue virus is concerned the cases also seem to be on the rise in Mansehra of the Khyber-Pakhtunkhwa province. The major cities appear to be bracing for yet another dengue outbreak as health experts have warned of the increased presence of dengue larvae following the recent spell of rain in the province.
Dengue serotype 2 is the most prevalent circulating serotype in Pakistan, with few reported cases of serotype 3. In 2017, the KP faced an epidemic of dengue, with 18,856 cases and multiple deaths, which was attributed to a different lineage of dengue virus serotype 2.
This lineage entered Pakistan from China around 2016 and spread in 2017. Vectors of dengue virus are mosquitoes of the Aedes genus, which are capable of transmitting other viruses, such as chikungunya, Zika, and yellow fever.
Vector populations are increasing in areas around the world. Other global change factors – including the growing population and increasing agriculture, deforestation, and urbanisation – equally and substantially contribute to the spread of mosquitoes.
Clearly, Pakistan has all the elements required for a rise in the number of infections transmitted by mosquitoes.
Inaction
The Punjab government has yet to mount any serious effort to stop fast transmission of dengue because of the tardy work to destroy the breeding grounds of mosquitoes spreading the virus.
Water accumulated alongside the roads on green belts, government offices, private buildings and residential areas after the spell of rains in the province. But the teams formed to control dengue visited very few places to check breeding of larvae.
The provincial government was supposed to establish dengue cells comprising public health experts besides constituting teams of the police and district government officials to conduct raids to book those violating the Standard Operating Procedures (SOPs) or guidelines.
The official data showed it never happened, resulting in spread of the dengue virus especially in areas having dense population.
The situation turned worse when the Punjab health department reportedly received complaints against surveillance workers of extorting money from traders by threatening to close their businesses because of the presence of the larva.
The upscale areas of Lahore appeared at higher risk as around 80 percent of dengue patients in Lahore were from the Defense, Gulberg, Bahria Town, and Model Town areas.
Challenges
Bed occupancy of High Dependency Units (HDUs) of the hospitals in the province, designated for the critical care of dengue patients with complications, is reaching full capacity.
The government has established a field hospital at Expo Centre in Lahore that is proving helpful for the people but it should also focus on the other hospitals where the staff members are not taking the matter seriously.
A district government official alleged that thousands of dengue workers recruited on a political basis, especially in Lahore, were responsible for the failure of the recent campaigns against the disease.
The rise in dengue cases is intensifying across Punjab. In addition, it is highly important that all people take care of cleanliness and avoid throwing garbage in public places. The people should be more responsible and active to save themselves from the dengue virus.
Misperception
Health experts have issued a public-service message underlining the need to prevent misinformation about dengue and encourage people to take precautionary measures.
For example, many people believe that the dengue mosquito is active only at dawn and dusk. But research suggests that the Aedes mosquito, also responsible for the spread of dengue, bites during the day as well, especially two hours after sunrise and before sunset.
Immediate action is needed to ensure that the outbreak is contained as soon as possible and does not reach the near-epidemic proportions of 2019, when cases in Punjab rose to more than 8,670 with over 50,000 reported from all of Pakistan.
New strains
All four strains of the dengue virus – DENV-1, DENV-2, DENV-3, DENV-4 – are circulating in Lahore, which means the number of critical patients and deaths may increase. The incidence of DENV-1 is four percent while DENV-4 has been recorded in nine percent of patients.
Additionally, four percent of those infected in Punjab have both DENV-2 and DENV-3 viruses, which may have had an impact on mortality rates. Infection with one strain does not provide immunity against other strains so that person living in an endemic area can have up to four dengue infections during his or her life span.
Risk of dengue transmission is present throughout Pakistan at elevations below 2,300 m (7,500 ft), including the city of Islamabad. Transmission typically occurs between July and November. This is the first time dengue has been reported in the tourist destinations.
Symptoms
Dengue is a disease caused by a virus spread through mosquito bites. The disease can take up to 2 weeks to develop with illness generally lasting less than a week. In some cases, Dengue infection is asymptomatic.
Those with symptoms get ill between 4 and 7 days after the bite. The infection is characterized by flu-like symptoms which include a sudden high fever coming in separate waves; pain behind the eyes; muscle, joint, and bone pain; severe headache; and a skin rash with red spots.
Treatment includes supportive care of symptoms but there is no antiviral treatment available. Health effects from dengue include fever, headache, nausea, vomiting, rash, muscle and joint pain, and minor bleeding.
Dengue can become severe within a few hours. Severe dengue is a medical emergency, usually requiring hospitalisation. In severe cases, health effects can include haemorrhage (uncontrolled bleeding), shock (seriously low blood pressure), organ failure and death.
Prevention
The people should take meticulous measures to prevent mosquito bites during the daytime. They should use a repellent containing 20-30 percent DEET or 20 percent Picaridin on exposed skin.
Wearing neutral-coloured (beige, light grey), long-sleeved and breathable garments is also helpful in the current situation. They should get rid of water containers around dwellings and ensure that door and window screens work properly.
They should not leave stagnant water lying anywhere in or around the house. Mosquitoes live and breed on stagnant water, whether it is dirty or clean. They should keep the doors and windows of the house closed, mostly early in the morning and during the evening.
Using anti-mosquito sprays especially in the corners of the house is highly effective in killing the hidden mosquitoes.
Advisory
The National Institute of Health’s Field Epidemiology and Disease Surveillance Division has issued an advisory regarding prevention and control of dengue virus across the country.
The objective of the advisory is to sensitise human and animal healthcare authorities to further strengthen and improve the level of preparedness in prevention and control of the disease.
According to the advisory, dengue is a viral disease transmitted by mosquitoes of the genus Aedes. It is endemic to almost all geographical regions of Pakistan and there is substantial evidence that its multiple serotypes are circulating in different areas of the country.
Despite patchy surveillance, a total of 53,498 cases with 95 deaths due to dengue fever were reported in 2019 while 6,016 cases were reported in 2020, and 3,795 cases have been reported in 2021 up to September.
Climate change
Mosquito distributions are highly dynamic in space and time, as their life cycles are short and heavily influenced by environmental variation. The incidence of dengue has increased 30-fold over the past 50 years.
Climate is an important driver of the current distribution and incidence of dengue. The geographic ranges of the primary Aedes mosquito are expanding. This may lead to a greater burden of dengue in lowand middle-income countries like Pakistan.
The latest models suggest that new geographic areas along the fringe of current geographic ranges for Aedes will become environmentally suitable for the mosquito’s lifecycle, and for dengue transmission.
Climatic changes resulting in increased temperature and rainfall, together with urbanisation, may therefore be associated with increased dengue incidence and outbreak risk.
It is very difficult to control or eliminate Aedes mosquitoes, and after their introduction, they can become established if climatic and ecological conditions are suitable. They adapt to human environments and their populations often recover from natural disturbances such as drought or human control measures.
