Interpretation
Since the peak of the outbreak, methods effectively prevent COVID-19
recurrence have been the focus. Studies have shown that asymptomatic
infections are contagious [3]. Asymptomatic carriers can also be a
source to propagate the outbreak. The literature reports SARS-CoV-2 test
that turned positive in a discharged patient with COVID-19 [4].
Hospital outpatient clinics, which are specialized for epidemic
prevention, are the first barrier to prevent infection in the hospital
because inpatients are diagnosed here and admitted to the hospital.
Officially released information from Wuhan indicated that there were
still asymptomatic infections found every day as of May 8, 2020. The
fact that no NAT-positive cases were found in our study may be related
to our visit procedure, which includes monitoring body temperature and
seriously inquiring about past histories. Three patients with COVID-19
discovered in the recovery period had concealed a history of infection
at the time of their visit. When the test results indicated
abnormalities (2 patients were NAT positive, 1 patient was IgM-positive
and IgG-positive), the patients confessed their medical history.
Patients are required to sign a notification form confirming that they
have are no COVID-19 symptoms or exposure history.
It is worth mentioning that
online telemedicine has played an
important role in the diagnosis and treatment of obstetrics and
gynecology patients. Our online clinic services cover video
consultations, text-picture counseling, and medicine delivery. This
approach reduced the number of people congregating in the hospital after
the peak of the outbreak.
The IgG-positive individuals with no history of COVID-19 probably had
recovered asymptomatic SARS-CoV-2 infections. A previous study reported
that 10.26% of patients in the hospital were IgG positive but were all
IgM and NAT negative [5]. In this study, the IgG positive rate of
3.140% (33/1051) was lower than that in other reports. The possible
cause is that the patients were all female, and most of them had
infrequent social interaction because they were unwell. Studies have
reported that 13.5% of pregnant women in New York were
SARS-CoV-2-positive but asymptomatic at the peak of the outbreak
[6]. No NAT positivity was found, and the IgM positivity rate in the
325 patients who were pregnant in our study was 0.615% (2/325). At the
same time, our study suggests that abnormal uterine bleeding and
gynecological tumor patients may be more susceptible to COVID-19 and
deserve our research attention. Despite the low number of cases,
follow-up information suggests that IgM-positive patients are less
contagious.
Current methods of screening for SARS-CoV-2 infection are the NAT, chest
CT scan and serological testing. Our results suggest that CT has limited
performance accuracy for SARS-CoV-2 infection screening in obstetrics
and gynecology outpatients without a medical or exposure history of
COVID-19 or suspected symptoms. In areas where testing resources are
limited, a strict visit procedure is even more important, and a primary
screening with serological testing alone or in combination with the NAT
might be sufficient to triage the obstetrics and gynecology outpatients
without a contact history or symptoms of SARS-CoV-2 infection.