A study conducted by the researchers at ICMR showed that the monkeypox infection can frequently present itself with atypical symptoms and complications that were not observed in previous epidemics or cases in endemic areas. Hence, oropharyngeal swabs (OPS), nasopharyngeal swabs (NPS), and urine samples should be considered critical specimens for monkeypox diagnosis in cases with no active skin lesions. So far, 11 cases of monkeypox have been reported in India, five from Kerala and six from Delhi.

According to the study titled, "A fatal case of monkeypox virus infection from Kerala, India, 2022," the first known case of infection highlighted the importance of maintaining a high index of suspicion to diagnose MPXV in those presenting with atypical manifestations, fever, etc. The study noted that a 22-year-old immunocompetent male with no significant medical history was admitted in an unconscious state to a private hospital in Kerala following a single episode of acute-onset generalized seizures. Meanwhile, the patient developed a fever and headache while in the UAE, followed by the development of painful right inguinal lymphadenopathy with pus discharge, for which he sought medical care.

Later, he returned to Kerala after being partially relieved of his symptoms but complained of worsening pain in the right inguinal area while playing football. On consulting a surgeon, the patient was diagnosed with hidradenitis suppurative. He continued to report fatigue and low-grade fever, which were not associated with persistent headache, alteration of the sensorium, loss of appetite, or weight. Serological tests for HIV, Hepatitis B, Hepatitis C, and syphilis were negative. According to the study, he developed coagulopathy and acute kidney injury over the next 48 hours, followed by cerebral edema, and was intubated and mechanically ventilated. Despite anti-cerebral edema measures, he succumbed to the infection on July 30. 

(Source: https://www.thehindubusinessline.com/news/science/oral-nasal-samples-necessary-for-monkeypox-diagnosis-icmr-study/article65893321.ece )