Q&A: Investigating emerging illness in India requires ‘very thorough process’

Preliminary blood tests from individuals sickened by an unidentified illness in southern India showed high amounts of lead and nickel, but no evidence of a viral infection, according to the BBC.

Health officials there have also ruled out water contamination or air pollution, the BBC stated.

The unidentified illness in the southern Indian state of Andhra Pradesh has sickened hundreds of individuals, with symptoms that included seizures, nausea and loss of consciousness. One patient who contracted this novel illness died, according to CNN. However, that patient had a fatal but unrelated cardiac arrest.

Currently, there is “not much information” about the emerging illness in India, according to Carlos A. Pardo-Villamizar, MD, professor of neurology and pathology at Johns Hopkins University School of Medicine and director of the Johns Hopkins Transverse Myelitis Center. Healio Neurology asked Pardo-Villamizar about the most pressing questions for health officials in India and the context of another novel illness in the setting of the COVID-19 pandemic. India has more than 9.7 million COVID-19 cases as of Dec. 9, 2020, according to the Johns Hopkins COVID-19 tracking map, second only to the U.S. in the number of cases.

Q: What do we know about this novel, unidentified illness?

I don’t have too much information about this emerging situation. I’ve listened to the news reports from India, but I don’t have any additional information or specific medical information. I’ll share my view, my perspective as a neurologist who works on emerging viral disorders.

Q: What are the immediate priorities for health investigators ?

A: When anything like this happens around the world, when there is a cluster of acute illness in which there are elements of neurological symptoms like dizziness, headache, nausea, vomiting or even seizures, the first thing that comes to mind is a potential infection of the brain or other type of acute infection that may be causing meningitis or another neurological complication like encephalitis. In that setting, we need to first understand the clinical profile of the illness. In an outbreak like this that involves more than 300 people suddenly, one that involves symptoms of nausea and vomiting and some neurological manifestations, we first need to ensure that there is no viral agent or infectious agent. Infectious agents include viruses or bacterial diseases.

The second line of investigation should focus on locating the presence of toxicants in the environment in which the people experiencing the symptoms live. From that perspective, there is the need for a very careful assessment of potential environmental factors. It is important because there are many toxicants, many pesticides, many materials used in agriculture, particularly in tropical regions, that have the potential to cause a neurotoxic effect. Those two potential causes are the first in line to be investigated — infectious causes and toxic causes of this problem.

From an epidemiological point of view, the first and most urgent step is to establish a very clear profile of the clinical problems these patients are experiencing: We need to identify the main symptoms associated with this illness, whether there is any evidence at all of a clear infectious profile. For example, if we think that this may be associated with an infectious disorder, patients with an infectious disorder frequently present with fever and may present with other systemic manifestations of infection in the form of a skin reaction, pulmonary symptoms, diarrhea and gastrointestinal symptoms. When we have a good clinical profile, we may need to try to identify other elements of the illness. Those are provided by blood testing; if there is any concern about infections, blood tests may be helpful. If there is any concern about an infection in the brain, imaging of the brain may be needed. Importantly, identification of potential infectious agents in the spinal fluid of these patients is needed. We must engage in a very, very thorough process of identifying the causes of this outbreak.

Q: How does the COVID-19 pandemic impact the examination of this new illness?

A: Everyone is thinking about COVID-19 all the time now, but it is important to remember that in tropical regions of the world, there are other infectious agents that are still very prominent; the active process of transmission of those infectious agents continues despite COVID-19. For example, in many areas of India, including areas like the one where this outbreak is happening, there are many infectious disorders that are prominently associated with other viral infections, including infections transmitted by mosquitoes. In those areas of India, this includes dengue and chikungunya. Yes, we are obviously concerned about COVID-19, but we need to remember the possibility that there are other viral or bacterial infections that are more prevalent in the areas affected by the outbreak that may be involved here.

There is also the possibility that there are other emerging viral factors. In India, for example, there are some outbreaks of other rare disorders. There was an outbreak of nipah virus infection in 2018 that produced significant concerns. Fortunately, it was concentrated to a very reduced area of India. But there are possibilities that need to be evaluated outside of COVID-19.

My understanding from the news reports is the patients affected by this new emerging illness were evaluated thoroughly for COVID-19 with negative results. Many of these patients were also evaluated for dengue, chikungunya, the viral illnesses that are prevalent in that region. The need for a very comprehensive assessment of other infections is there. That is the next step that the health authorities in that state of India need to focus on.

Q: What would be the impact of two emerging infections at the same time?

A: Concerns about managing two emerging infections at the same time is a very good point. That should be on the radar of the epidemiologists and the investigators in the region. There are several things that may happen during an outbreak; the possibility of coinfections is high, particularly with the pandemic. What we know about the epidemiology of this outbreak is still minimal, but my understanding is that the illness is affecting people of all ages, including children. It is a very unusual outbreak and, until we have more specific details, we are not able to speculate about potential causes.

We don’t have much information yet, but we are very curious about the neurological features of this illness, whether these patients are experiencing seizures or other types of neurological manifestations. We are very anxious to learn more about the clinical picture, particularly with a focus on the neurological manifestations of this outbreak.

• Johns Hopkins University of Medicine Coronavirus Resource Center. https://coronavirus.jhu.edu/map.html. Accessed Dec. 9, 2020.