SARS-CoV-2 RT-PCR test, false result problem, public risk assessment and reliability of epidemiology statistics.

Dear Editor,

There are many interesting issues regarding risk management and assessments for COVID-19. An interesting topic to be addressed would be the problems and pitfalls of the actual situation. First, for any guidelines or protocols to be useful, they must be implemented and used. In developing countries, the local health centre administrator may not follow best practices and, as a result, may cause difficulty for practitioners. For example, some administrators might care about patient satisfaction more than social distancing, which is crucial for infectious disease prevention for the health care staff. Second, the availability of personal protective equipment is usually a big problem. During this crisis, supply shortages are common. Third, the risk assessment is useful. However, there are usually problems with the epidemiological data for diseases. In many developing countries, local public health policies may pretend to save face by denying that there are any cases, when real cases are disguised by data and bias.

Additionally, there is difficulty detecting asymptomatic cases or cases with atypical presentations. Nevertheless, the available diagnostic tool might have the problem of false-negative results. These problems are common and they result in unreliable data that are later used in risk assessments and preventive action planning. These problems and pitfalls are from the actual clinical situation.

A very important point should be mentioned about the reliability of the diagnosis for public policy management. In the report from Romania, it was noted that many SARS-CoV-2 RT-PCR tests have been administered to coordinate containment of COVID-19. Increased effort is necessary to further improve the system. In fact, the diagnostic property of the particular SARS CoV-2 test can directly affect the epidemiology statistics. Generally, the molecular SARS CoV-2 test is the standard test in many settings. There is a chance of either false-negative or false-positive results. The diagnostic sensitivity of the test is an important determinant for the diagnostic ability of positive cases. In an early infection, with a very low viral level, it is possible that the test cannot detect the infection; in such cases, the test can result in a false-negative result. Additionally, a pre-analytical problem can result in a false-negative result. The best example is poor specimen collection. Also, there might be a false-positive result due to the contamination. In a developing country with poor laboratory quality, this problem might occur. A good example is the local news coverage of a cluster of false positive COVID-19 cases from Southeast Asia. In that situation, the rate of false results in sample testing was equal to 0.2%. The remaining nucleic particle in a patient recovering from infection might cause difficulty in correctly diagnosing whether it is a re-infection Case or not. This is usually a problem in the post-quarantine detection of an RT-PCR positive case. The situation becomes more complex when a country claims that there is no infection in that country. A true positive result might be perceived to be a false positive due to remaining nucleic acid or it might be considered an imported case from another country, although the case was detected after the standard quarantine process. Standardization of the diagnosis and transparency of local public health departments are important determinants of the reliability of epidemiology statistics.

In conclusion, diagnosis and risk assessment should not just depend on the result of the diagnostic test. Local health authorities need to be proactive and vigilant when considering personal history and contact exposure. The rate of testing and the availability of the tests are among the other essential factors to consider.

Source of funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Conflict of interest

The authors have no conflict of interest to declare.

Ethical approval

There are no ethical or financial issues, conflicts of interests, or animal experiments related to this research.

Authors' contributions

BJ and VW conceived and designed the study, conducted research, provided research materials, collected and organised data, analysed and interpreted data, and wrote the initial and final draft of the article. All authors have critically reviewed and approved the final draft and are responsible for the content and similarity index of the manuscript.