For years, mosquito-borne diseases such as dengue, malaria and chikungunya have been closely associated with the monsoon season. While rainfall, humidity and stagnant water can significantly increase mosquito breeding, the risk is no longer restricted to a few months of the year. Changing weather patterns, rising temperatures, urbanisation and water-storage practices are creating conditions that can allow mosquitoes to remain active for longer periods. The World Health Organization also notes that climate and environmental changes can influence the distribution and length of mosquito activity.
When a Fever Needs Clinical Attention
The Aedes mosquito, which transmits dengue and chikungunya, is particularly well adapted to urban environments and can breed in small water-filled containers around homes and workplaces. In cities, mosquitoes do not necessarily need large pools of stagnant water to breed.
This changing pattern also has implications for diagnosis. A fever occurring outside the monsoon period may often be assumed to be a routine viral infection. However, when fever is accompanied by severe headache, body ache, pain behind the eyes, nausea, vomiting, rash or fatigue, a mosquito-borne illness may need to be considered depending on the patient's symptoms. Dengue, in particular, can range from a mild illness to severe disease requiring hospital care.
Why Recovery From Fever Does Not Always Mean Recovery
Another important aspect is that improvement in fever does not always mean that the patient is completely out of danger. In dengue, warning signs of severe disease can appear around the time the fever begins to settle. Severe abdominal pain, persistent vomiting, bleeding, breathing difficulty, unusual weakness, drowsiness or cold, clammy skin require prompt medical attention.
Also the clinical risk is not uniform across patients. Young children, older adults, pregnant women and people with certain underlying medical conditions may require closer clinical monitoring depending on the infection and their overall health status. A patient's previous history of dengue can also be clinically relevant, as a subsequent infection with a different dengue serotype can increase the risk of severe disease.
Prevention Needs to Be a Year-Round Effort
Prevention therefore needs to move beyond a seasonal approach. Regularly checking homes, workplaces and surrounding areas for stagnant water can help reduce mosquito breeding. Water-storage containers should be properly covered, plant trays and other water-holding containers should be emptied regularly, and discarded tyres, bottles and other items that can collect water should be removed. Personal protection, including mosquito repellents, appropriate clothing, window screens and mosquito nets where appropriate, can further reduce exposure.
For individuals, the key message is simple: do not rule out a mosquito-borne infection simply because it is not the monsoon season. Persistent or worsening fever should be medically evaluated, particularly when accompanied by other concerning symptoms.
Mosquito-borne diseases may show seasonal peaks, but prevention and awareness cannot be seasonal. As environmental and climatic conditions continue to change, maintaining vigilance throughout the year will be important for reducing transmission and ensuring that patients receive timely medical care.
Disclaimer: The views expressed in this article are of the author and not of Health Dialogues. The Editorial/Content team of Health Dialogues has not contributed to the writing/editing/packaging of this article.
