Vector-borne diseases and respiratory infections ruled the roost in 2023 even as newer and milder strains of Covid-19 kept trickling in. Dengue outbreaks in many parts of the world including India due to global warming and excessive rainfall were reported apart from other vector-borne illnesses like zika and chikungunya. According to European Centre for Disease Prevention and Control, in 2023 until the beginning of November, over 4.5 million cases and over 4,000 dengue-related deaths have been reported from 80 countries/territories globally. Many countries saw worst dengue outbreak ever this year. As the year comes to a close, a surge in cases of walking pneumonia, commonly referred to as mystery pneumonia, is leading to increased hospitalisations in China, the US, and other areas. This upswing raises concerns about the potential emergence of another pandemic. (Also read | Year Ender 2023: 5 ways hybrid work model affected marriages)

"In 2023, a spectrum of diseases captured headlines globally, highlighting the ongoing challenges in public health, says Dr Manjusha Agarwal, Senior Consultant Internal Medicine Global Hospitals Parel Mumbai as she talked about health concerns that demanded attention from dengue to mysterious pneumonia.

1. Dengue outbreaks

Dengue fever continued to be a significant public health concern in various regions, with outbreaks causing a surge in reported cases. Strategies for mosquito control and public awareness campaigns remained in focus.

New research at the Rajiv Gandhi Centre for Biotechnology and published in The Federation of American Societies of Experimental Biology has found out that dengue becomes more severe in animal models when its virus is exposed to higher temperature. Global warming could be changing the disease dynamics, making it more severe.

2. Mystery pneumonia cases

Towards the end of the year, mysterious pneumonia cases have surfaced in China, USA and other parts of the world, drawing attention due to the unknown origin of the disease and the need for swift identification and containment. It is affecting children and leading to their hospitalisation. Investigations and collaborative efforts among health agencies were initiated to understand and address the situation.

The children suffering from the disease are presenting with high-grade fever without any other symptoms and further radiological investigations have revealed lung lesions. Some patients have been hospitalised for further management. Experts say the surge in cases of this 'undiagnosed pneumonia' could be due to a phenomenon called 'immunity debt' after lifting of lockdown restrictions in the peak season of respiratory illnesses.

3. Emerging infectious diseases

Novel infectious diseases and emerging pathogens raised alarms, underlining the importance of global preparedness and surveillance. Vigilance in monitoring and responding to potential pandemics remained a key priority.

4. Antibiotic resistance challenges

The escalating challenge of antibiotic resistance gained prominence. Discussions centred around the need for sustainable practices in healthcare to combat the growing threat of drug-resistant infections.

5. Continued battle against Covid-19

The fight against Covid-19 persisted, with updates on vaccination efforts, emerging variants, and ongoing research to enhance treatment options and pandemic preparedness.

6. Mental health issues

While not a traditional infectious disease, mental health garnered increased attention. The impact of the pandemic on mental well-being led to a heightened focus on mental health awareness, resources, and support systems.

7. Vector-borne diseases

Beyond dengue, other vector-borne diseases like Zika and Chikungunya remained on the radar. Climate-related factors and urbanization contributed to the continued spread of these diseases.