PRESS BRIEFING BY THE UNITED NATIONS INFORMATION SERVICE
21 July 2023
Update on Dengue Outbreaks
Raman Velayudhan, Head of the Unit coordinating the dengue and arbovirus initiative, Global Program on Control of Neglected Tropical Diseases, World Health Organization (WHO), said dengue was the most common viral infection that spread from mosquitoes to people. Most people who contracted dengue for the first time did not have symptoms, and most of those who did, recovered in one to two weeks. However, some people who contracted dengue repeated times had severe symptoms, and the death toll worldwide was high.
It was treated with medicines to lower the temperature and body pain, but there was no specific treatment. When there were outbreaks, dengue could draw precious resources from the health system, adding a further burden.
Dengue was spread by the Aedes species of mosquito. The disease was more common in tropical and subtropical climates. Its incidence had grown dramatically worldwide in recent decades. Cases reported to WHO had increased from half a million in 2000 to over 4.2 million in 2022, a more than eight-fold increase in two decades. The number of actual cases could be much higher. About half of the world's population was now at risk of dengue, with an estimated 100 to 400 million infections occurring each year.
The Americas region had reported 2.8 million cases and 1,280 deaths in 2022. This increasing trend was continuing in 2023, with already close to three million cases reported. The southern spread of cases in Bolivia, Paraguay and Peru was a growing concern.
In the European region, the Aedes mosquito was established in over 24 countries, which had reported dengue and chikungunya regularly since 2010.
In the Middle East, a high number of cases had been reported from Sudan, with 8,239 cases and 45 deaths since July 2022. In recent weeks, dengue cases had been reported in Egypt. Trends in Asia were also worrying. Asia usually represented around 70 per cent of the global disease burden.
There are several factors driving this spread. These included increased movement of people and goods; urbanization and associated problems of water and sanitation; and continuing spread of the mosquitoes to more regions and countries. There were also issues linked to climate, such as high precipitation, increased temperature and water scarcity, which favoured mosquitoes' breeding. The virus and the vectors multiplied faster at higher temperature.
Several new tools were under development that provided greater hope in preventing and treating dengue, such as better diagnostics and antivirals under clinical trial. One vaccine was in the market, and two were being trailed and reviewed. Vector control tools included “Wolbachia” population replacement and population suppression models, the “sterile insect” technique and spatial repellents.
WHO was providing technical support to help countries respond to the outbreak and enhance cross-border exchange of information. Community action was also needed for preventing mosquito breeding, raising awareness about dengue and encouraging those affected to seek medical care. WHO was also implementing an integrated strategy for control, with guidance for clinical management.
As the rainy season and El Niño commenced, there was a risk that Asian countries could experience a severe dengue outbreak. Dengue outbreaks usually happened around eight weeks after the monsoon season, so the next outbreak was coming soon. Health authorities were encouraging local agencies to reduce the breeding of mosquitoes.
WHO was working closely with countries in the Global Arbovirus Initiative to join forces to control some of the most burdensome diseases spread by mosquitoes. It was encouraging countries to focus on the most efficient actions to save lives and prevent disease.
In response to questions, Dr. Velayudhan said after the first wave of dengue in new areas, there was a possibility of 80 per cent of people having very mild symptoms. It was important to detect the first wave, as a few years down the line, there was a potential for more severe cases when future waves hit. Populations needed to be protected against those severe cases.
This was the beginning of the monsoon season, which had hit India as well as several other States. The stakes were high in India, with reports of dengue increasing. There was a need to prevent breeding by taking measures such as cleaning out stagnant water around houses. Such actions could reduce the number of cases.
Cases in Africa were a matter of concern. The WHO Regional Committee for Africa had released the Framework for the Integrated Control, Elimination and Eradication of Tropical and Vector-Borne Diseases in the African Region. There were at least 200,000 cases per year reported in Africa. This year, there were already reports in countries such as Kenya and Sao Tome and Principe. Dengue in Africa had been masked by other diseases such as malaria in the past, but with the decrease in malaria, dengue cases were becoming more evident. There was a need to continue to improve detection mechanisms.
Mosquitos with dengue bit during the day, so mosquito nets had limited effects. Other preventative measures such as spraying repellents needed to be taken in schools and homes. There was no direct drug intervention for dengue available yet, only medicines for reducing the effects of the disease. Tests needed to confirm the disease took two to three days. Governments needed to make rapid tests available and increase diagnostic capacities.
The vaccine for dengue on the market had been registered in 20 countries. It had three doses and worked well for people who had had the disease once. The vaccine had an average 65 per cent efficacy, varying depending on the variety of the disease.
On average, the highest number of confirmed deaths per year from dengue was around 6,000, but it was estimated that there the number was much higher, possibly around 40,000 to 70,000 deaths. The WHO hoped to reduce deaths further.
Climate change created excess rainfall, which led to more stagnant water in which mosquitos could breed. This was a major challenge. Rainfall levels needed to be monitored and stagnant water removed. Mosquitos were able to hide in cooler areas to escape the heat during heatwaves. After the current heatwave, there would be rainfall, which would create more breeding sites for mosquitos. In communities where water was being stored, it needed to be covered well to prevent breeding.
Dengue had four closely related viruses. If you contracted one virus, you were immune from that virus for your lifetime. However, if you subsequently contracted other dengue viruses, you could potentially develop serious symptoms.
Body and clothing repellents, electronic mats, coils and long-sleeved clothing were effective in preventing mosquito bites. Mosquitos usually did not enter air-conditioned areas, and shutting windows and doors was also effective.
Historically, dengue started in 1953, with seven or nine Asian countries reporting dengue. Since then, numbers had increased, with around 2.5 million cases reported in 2019. More and more regions were now being affected, and WHO predicted around four million cases for this year. However, the number of cases would depend on what happened in the next six months.
There were plant-based repellents available, some of which were effective. Users needed to follow labels’ instructions for such products. Their effects lasted for shorter periods than chemical-based products.
Alessandra Vellucci, Director of the United Nations Information Service (UNIS) in Geneva, said the UN Special Envoy for Syria, Mr. Geir O. Pedersen, would brief the Security Council on Monday, 24 July at 4 p.m. The briefing was currently scheduled as open, and a transcript would be delivered after the conclusion of the briefing.
The UN Food Systems Summit +2 Stocktaking Moment would also open on Monday, 24 July at 2:30 p.m. The high-level event would build on the momentum of the 2021 Food Systems Summit and create a conducive space for countries to review progress on commitments to action and identify successes, enduring bottlenecks and priorities in order to close the implementation gap for food systems transformation.
The three-day meeting in Rome would further highlight the central role of food systems transformations in overall advancement of the Sustainable Development Goals ahead of the SDG Summit in September 2023. The meeting would advocate for urgent action at scale, building on the latest evidence that sustainable food systems contribute to better and more sustainable outcomes for people, planet and prosperity, leaving no one behind.
The high-level opening ceremony would see the participation of the Prime Minister of Italy, the Director-General of the Food and Agriculture Organization, the President of the International Fund for Agricultural Development and the Executive Director of the World Food Programme.
More than 1,200 participants from 161 countries, including 19 Heads of States and Governments, 100 minister-level delegates and more than 450 Non-state Actor (NSA) delegates would attend the event. The main sessions would be broadcast on UN Web TV.
Ms Vellucci added that the Secretary-General held a briefing on 20 July to present to Member States a “New Agenda for Peace”. The briefing gave States a vision of multilateral efforts for peace and security, based on international law, for a world in transition.
The UN Office at Geneva had just published its annual report for 2022, which could be viewed on the UN Geneva website. The report presented an overview of activities occurring at UN Geneva in 2022. There was a chapter on communicating UN work and values. Ms. Vellucci thanked all journalists accredited to UN Geneva for their coverage of the Office’s activities last year.
Fionnuala Ní Aoláin, the UN Special Rapporteur on the promotion and protection of human rights and fundamental freedoms while countering terrorism, would hold a hybrid press conference on Friday, 21 July 2023 at 12 p.m. on returns and repatriations from conflict zones. Joining her would be Anne Charbord, Senior Legal Advisor of the Special Rapporteur.
The Committee against Torture was continuing its 77th session in Geneva, and would conclude its review of the report submitted by Spain this afternoon at 3 p.m. Next Monday starting at 11 a.m., the Committee would hold a short, public meeting to discuss reports on follow-up to its concluding observations, on individual communications (complaints) and on reprisals against persons having collaborated with the Committee.
The Human Rights Committee would meet on Monday, at 3 p.m., to adopt reports on the follow-up to it concluding observations regarding countries reviewed during previous sessions.
Also, on Wednesday, 26 July 2023 at 1:30 p.m., the Human Rights Committee would hold a hybrid press conference to present its findings on the reports of Brazil, Burundi, Colombia, Cyprus, Lesotho, State of Palestine and Uganda, which it has reviewed this session. Speaking would be Committee Chair Tania María Abdo Rocholl and other Committee members.