Environmental surveillance is the process of monitoring the wastewater (sewage) generated by a population to look for contaminants. It is possible to detect several kinds of infections circulating in the community, through testing wastewater.
There is evidence to suggest that community prevalence, early warning signals are possible through routine monitoring of wastewater.
Infectious Disease Surveillance
Surveillance & Prediction of Outbreaks Due to
According to the WHO, wastewater surveillance can establish the presence of SARS-CoV-2 across an entire community. As wastewater contains waste from many sources, samples that are examined for the presence of SARS-CoV-2 represent the combined collective signature of communities regardless of health status (symptomatic, asymptomatic, pre-symptomatic, or recovered) or access to and use of clinical testing.
Furthermore, wastewater, as a representative of community-based urine and faecal samples, could be extremely useful in understanding the occurrence and outbreaks of several water-borne pathogens , including bacteria (Salmonella spp., Vibrio cholerae, Shigella spp., Campylobacter spp.), viruses (norovirus, sapovirus, adenovirus, poliovirus), protozoa (Cryptosporidium Waterborne diseases which are of concern with respect to public health in India include diarrhea, dysentery, jaundice, and cholera).
Among them, diarrheas is listed as the third leading cause of death among children in India is the cause of 13% of deaths among children below 5 years of age and leads to an estimated 300,000 deaths among children in India each year . The information obtained from this surveillance can provide early warning signs to the government about such outbreaks, and enable actions to mitigate and prevent adverse public health outcomes.
The Centre for Disease Control states that in India, bacteria causing common infections like urinary tract and bloodstream infections are becoming increasingly resistant to nearly all antibiotics. In addition, the ongoing SARS-CoV-2 pandemic has led to the rapid development of vaccines and antivirals to treat SARS-CoV-2 infections. However, along with these developments comes the threat of the emergence of antibiotic resistance against drugs like carbapenamases and infections due to the increased use of antibacterial cleaning products and therapeutics in hospitals.
Waste materials discarded from these sources in the environment can enter the water cycle, which in turn affects plants and, finally, humans. Conducting studies on antimicrobial resistance will help to enable policy and action change in the healthcare industry and ensure that healthcare institutions follow certain mandates to ensure the safe disposal of clinical waste into the environment.
Drug Testing/Abused Pharmaceuticals
Wastwater-based analysis has emerged as an effective method to analyze the presence of drugs and pharmaceutical compounds through analysis of wastewater samples. Studies on wastewater treatment plants in the Gurupura river near Mangalore have established the presence of drugs like Aspirin, Ibuprofen, Naproxen, Ketoprofen, and Diclofenac. Continuous discharge of NSAIDs into the river can result in adverse effects on the resident organisms. A city-wide surveillance program could provide insights on the presence of abused drugs and pharmaceuticals and lead to actions to combat drug abuse and address environmental pollution.
Currently, environmental surveillance is mostly used as an Early Warning System for the city administration. However, it can also be used in more closely looped targeted settings such as universities, townships, hospitals, which have their wastewater treatment plants. In addition to this, more environmental indicators such as air and water quality, treated wastewater quality can be studied to provide in-depth information about risk indicators for the residents, so that containment measures can be taken sooner. In other words, targeted settings can have an integrated surveillance system which can track multiple environmental indicators to provide extensive insights on the health risk which may be present within the campus.