tetano
Editor, Senior Moderator
Am J Infect Control
. 2020 Oct 6;S0196-6553(20)30898-1.
doi: 10.1016/j.ajic.2020.10.002. Online ahead of print.
The role of close contacts of COVID-19 patients in the SARS-CoV-2 transmission: an emphasis on the percentage of non-evaluated positivity in Mexico
Margarita L Martinez-Fierro[SUP] 1 [/SUP], Jorge R?os-Jasso[SUP] 2 [/SUP], Idalia Garza-Veloz[SUP] 2 [/SUP], Lucia Reyes-Veyna[SUP] 3 [/SUP], Rosa Maria Cerda-Luna[SUP] 4 [/SUP], Iliana Duque-Jara[SUP] 5 [/SUP], Maribel Galvan-Jimenez[SUP] 6 [/SUP], Leticia A Ramirez-Hernandez[SUP] 7 [/SUP], Andres Morales-Esquivel[SUP] 2 [/SUP], Yolanda Ortiz-Castro[SUP] 2 [/SUP], Jose R Gutierrez-Camacho[SUP] 2 [/SUP], Jos? J Valdes-Aguayo[SUP] 2 [/SUP], Jose R Vargas-Rodriguez[SUP] 2 [/SUP]
Affiliations
Abstract
Objectives: To determine the percentage of positivity of close contacts of coronavirus disease 19 (COVID-19) patients to depict the importance of asymptomatic infections in the patient-to-patient transmission of COVID-19.
Methods: One hundred subjects were included. Nineteen index COVID-19 cases and eighty-one traced close contacts were screened for coronavirus 2 of severe acute respiratory syndrome (SARS-CoV-2) using real-time reverse transcription-polymerase chain reaction (RT-PCR). Immunoglobulin M (IgM) and G (IgG) against SARS-CoV-2 were evaluated by rapid test.
Results: Thirty-four (42%) contacts in the study were positive for SARS-CoV-2. Twenty-three (67.6%) manifested less than two respiratory symptoms, and five (14.7%) remained asymptomatic. The average of positive contacts by index COVID-19 case (R[SUB]0[/SUB]) was 4.3 and the mean of time of positive COVID-19 test at sampling time was 18.9 days. Positive antibody test against SARS-CoV-2 was observed in 16% of the participants.
Conclusion: The proportion of close contacts of COVID-19 patients infected with SARS-CoV-2 (42%) and with less than two or with no respiratory symptoms (82.4%) was high in the study population. A low proportion of COVID-19 patients had a positive test for antibodies against SARS-CoV-2. The screening for SARS-CoV-2 in close contacts of COVID-19 positive patients should be encouraged to avoid spreading the infection and the expansion of the disease.
Keywords: COVID-19; SARS-CoV-2; antibodies; asymptomatic contact.
. 2020 Oct 6;S0196-6553(20)30898-1.
doi: 10.1016/j.ajic.2020.10.002. Online ahead of print.
The role of close contacts of COVID-19 patients in the SARS-CoV-2 transmission: an emphasis on the percentage of non-evaluated positivity in Mexico
Margarita L Martinez-Fierro[SUP] 1 [/SUP], Jorge R?os-Jasso[SUP] 2 [/SUP], Idalia Garza-Veloz[SUP] 2 [/SUP], Lucia Reyes-Veyna[SUP] 3 [/SUP], Rosa Maria Cerda-Luna[SUP] 4 [/SUP], Iliana Duque-Jara[SUP] 5 [/SUP], Maribel Galvan-Jimenez[SUP] 6 [/SUP], Leticia A Ramirez-Hernandez[SUP] 7 [/SUP], Andres Morales-Esquivel[SUP] 2 [/SUP], Yolanda Ortiz-Castro[SUP] 2 [/SUP], Jose R Gutierrez-Camacho[SUP] 2 [/SUP], Jos? J Valdes-Aguayo[SUP] 2 [/SUP], Jose R Vargas-Rodriguez[SUP] 2 [/SUP]
Affiliations
- PMID: 33035601
- PMCID: PMC7538376
- DOI: 10.1016/j.ajic.2020.10.002
Abstract
Objectives: To determine the percentage of positivity of close contacts of coronavirus disease 19 (COVID-19) patients to depict the importance of asymptomatic infections in the patient-to-patient transmission of COVID-19.
Methods: One hundred subjects were included. Nineteen index COVID-19 cases and eighty-one traced close contacts were screened for coronavirus 2 of severe acute respiratory syndrome (SARS-CoV-2) using real-time reverse transcription-polymerase chain reaction (RT-PCR). Immunoglobulin M (IgM) and G (IgG) against SARS-CoV-2 were evaluated by rapid test.
Results: Thirty-four (42%) contacts in the study were positive for SARS-CoV-2. Twenty-three (67.6%) manifested less than two respiratory symptoms, and five (14.7%) remained asymptomatic. The average of positive contacts by index COVID-19 case (R[SUB]0[/SUB]) was 4.3 and the mean of time of positive COVID-19 test at sampling time was 18.9 days. Positive antibody test against SARS-CoV-2 was observed in 16% of the participants.
Conclusion: The proportion of close contacts of COVID-19 patients infected with SARS-CoV-2 (42%) and with less than two or with no respiratory symptoms (82.4%) was high in the study population. A low proportion of COVID-19 patients had a positive test for antibodies against SARS-CoV-2. The screening for SARS-CoV-2 in close contacts of COVID-19 positive patients should be encouraged to avoid spreading the infection and the expansion of the disease.
Keywords: COVID-19; SARS-CoV-2; antibodies; asymptomatic contact.