Previous studies have predicted that as summer approaches, rising temperatures and humidity can slow the spread of the virus. But a study by JAMA Network Open, a sub-journal of the American Medical Association, a leading international medical journal, on March 30, local time, gave a wake-up call. Even when summer comes, be alert to the spread of close droplets and direct contact.
The study analyzed a case of a new coronavirus (SARS-CoV-2) cluster transmission in the bathroom, and the researchers noted that while high temperatures and humidity have some effect on inhibiting the spread of the new coronavirus, it is still unavoidable and the spread of transmission through respiratory droplets and direct contact.
The study found that a bath ingested patient with a history of Wuhan exposure to new coronary pneumonia in a bath ingress in Huai’an City, Jiangsu Province, infected 8 people in the high temperature and humidity environment.
The study was carried out by teams such as Huai’an First Hospital, Huai’an Fourth Hospital, Jiangsu Province Cancer Biomarker Prevention and Control Key Laboratory of Nanjing Medical University, and was conducted by the authors of the communication by Shen Hongbing, A member of the Chinese Academy of Engineering, President of Nanjing Medical University, and Wang Qilong, Director of the Laboratory of Huai’an First Hospital affiliated with Nanjing Medical University. Published in the form of research letter, entitled “Mye Transmission of Acute Time OfaY Time Syndrome Corona2 (SARS-CoV-2) in a Bath Public Center in Huai’an, Jiangsu Province, China.”
Previous studies have shown that in high temperatures and humidity, the rate of transmission of the virus is greatly reduced. Long-term discussions and research have gradually come to a recognized point: low temperature, low humidity air environment is an important factor in the spread of winter influenza and other viruses. Many studies have suggested that the new coronavirus will gradually disappear with the high temperatureand and humidity of the summer, as was the case with sars (Severe Acute Respiratory Syndrome) virus.
However, the new coronavirus, which is currently raging globally, is clearly more capable of transmitting than SARS and MERS (MERS) coronavirus, which has been identified as being transmitted through contact, droplets and manure, and has a longer incubation period, up to a maximum of nearly 40 days.
The new coronavirus may be more “sophisticated” than the known coronavirus, which the study suggests can still spread in high temperatures and humidity in the bath.
It is worth noting that one of the eight people in this study was a bathing centre worker. At the same time, the researchers also note that the route of transmission of the virus may also be respiratory droplets or direct contact, and that the study has been limited by the lack of detailed information on the routes of transmission in bath center patients.
But the incident still suggests that the clustered transmission of SARS-CoV-2 may occur in high temperatures and humidity, and the authors say the results provide potential epidemiological clues for further study of the new coronavirus.
1 person has been to Wuhan resulting in 8 people infected one after another, one of whom is an employee
The researchers analyzed information on the confirmed cases of nine men who were admitted to the same bathing center at Huai’an Fourth Hospital in Jiangsu province from January 25 to February 10.
The male bath ingester is about 300 square meters, with an indoor temperature range of 25 to 41 degrees Celsius and a humidity of about 60%. It contains a soaking pool, as well as a shower and sauna area.
The first patient, that is, Patient 1, had a history of exposure to Wuhan. He developed cough symptoms on 15 January, went to the bath ingress on 18 January to take a bath, began to have a fever on 19 January and was diagnosed with new coronary pneumonia on 25 January.
Patients 2, 3 and 4 bathed in the bathing centre on 19 January, patient 5 bathed in the bath on 20 January, patient6 and patient 7 bathed in the bath ingy centre on 23 January, and patient 8 bathed in the bath ingy centre on 24 January. They began to develop symptoms such as fever, cough, headache, chest tightness and diagnosed new coronary pneumonia with nucleic acid tests 6 to 9 days after going to the bath ingresss.
9 patients in chronological order of morbidity and diagnostic information, patient 1 date bar is marked red
It is worth noting that patient sin 9 of this cluster infection, a bathing centre worker, began to develop on 30 January. Except for the infection source patient 1, the remaining 8 patients have no history of Wuhan exposure.
The median age of the nine patients was 35 years (24-50 years). A total of 8 patients (89%) had fever symptoms and 7 patients (78%) had cough symptoms.
Three patients (33%) showed symptoms of weakness, 2 (22%) developed chest tightness and 1 case (11%) developed anorexia. No patients develop edgy, myalgia, nasal leakage and headache.
In addition, 9 patients (100%) had elevated C-reactive protein levels (100%), 3 patients (33%) experienced lymphocytes reduction, 3 patients (33%) elevated lactic acid dehydrogenase, and 2 patients (22%) with elevated glutamate acetaminophen.
Lung computed tomography scans of nine patients all observed glassy turbidity, and as of February 10, 2020, no patients needed respiratory support and none of the nine patients became seriously ill.
New coronavirus could spread in high temperatures and humidity
Clinical performance of 9 patients and relevant laboratory test results
The researchers noted that not all seven of the eight infected bathers showed up at the bath center on the same day as patient 1, and that three patients went to the bath five days after the patient had gone to the bathroom.
In addition, considering that one of these patients is a staff member of the bathing centre, at least some of these infected persons may have been infected through the staff member.
Previous studies have shown that in high temperatures and humidity, the rate of transmission of the virus is greatly reduced. However, from the results of this study, the spreadability of SARS-CoV-2 shows no sign of abating in warm and humid conditions, suggesting that SARS-CoV-2 may spread and cause infection in this environment.
The researchers also said that in this cluster infection, the transmission of the virus may also be respiratory droplets or direct contact. But the incident still suggests that the clustered transmission of SARS-CoV-2 may occur in high temperatures and humidity, and the authors say the results provide potential epidemiological clues for further study of the new coronavirus.
At the same time, the study has been limited by a lack of detailed information on the routes of transmission in bath centers.
Notably, on March 19, local time, two mites at the Massachusetts Institute of Technology (MIT) also studied the effects of the weather on the new coronavirus, and they published a paper on The SSRN, a preprinted version of the paper, “Will Corona Corona Corona MaxiVirus by Summer?” It is also pointed out that although the influenza virus has been shown to be affected by the weather, it is not clear whether the new coronavirus is also affected by a similar effect.
Their results show that, so far, 90 percent of the new coronavirus transmission has occurred in a certain temperature (3C-17C) and absolute humidity (4g/m3-9g/m3). The total number of cases in countries with average temperatures above 18 degrees C and absolute humidity (AH) greater than 9g/m3 between January and March was less than 6% of the global total.
Although the previous SARS coronavirus and other viruses reflect the characteristics of the disappearance with the warming of temperature, but the current scientific research on coronavirus and climate correlation is still to be studied in depth and clarity. The researchers stressed that the relationship between the number of new coronavirus cases and temperature and absolute humidity is close in terms of the current spread of the virus. However, the underlying reasons behind this relationship remain unclear, or even rule-out, without any impact.
They stressed that appropriate quarantine measures should be taken even in warmer and humid areas. But at the same time, the relationship between temperature and humidity and new coronavirus cases should be closely monitored, and if there is a strong environmental dependence on the transmission of the new coronavirus, this relationship should be used to optimize the outbreak mitigation strategy.