Familial clusters of the 2019 novel coronavirus diseases in Taiwan

Abstract

Dear Editor: We agree that home quarantine has been effective in preventing the early transmission of coronavirus disease 2019 (COVID-19) by Wang et al. [1]. As family clusters of COVID-19 with 9 and 11 family members infected in China [2,3], the increased risk of COVID-19 in family members is noteworthy with home quarantines. The outbreak of COVID-19 with 2,160,207 laboratory-confirmed patients diagnosed and 146,088 reported deaths globally on April 18, 2020, by WHO [4]. With the earlier implementation of measures in preventing imported cases, The Taiwanese government has implemented various measures including travel bans since Jan 23, 2020, and home quarantines since Jan 25, 2020 [5]. Total 398 (0.76%) patients were diagnosed out of 52,445 tested individuals in Taiwan with 6 (1.5%) reported deaths as of April 18, 2020 [5]. The investigation for all the confirmed patients by the Taiwan Center for Disease Control greatly helps the tracing of the possibly contacted people and quarantine of them. Of the 398 patients, 43 (10.8%) by 16 family clusters, with 14 (with traveling history together), 5 patients were infected by the spouse when with home quarantine and others (infection transmitted from another family) in each family, were noted (Table 1 ). Particularly, 5 patients were asymptomatic infections (4 Taiwanese No. 18, 92, 356 and 382, and one another foreign temporary caregiver (No.32) after taking care No. 27 for 6 days). It is noteworthy that foreign caregiver's infection implicates another kind of “family cluster” due to close contact and the “occupation acquired infection” which indicates an ominous omen in an emerging infection with home quarantine. Fortunately, there is no new patient who is the caregiver in Taiwan until now [5]. Since only 55 (13.8%) of 398 patients were locally transmitted which may implicate the effective measures to protect the human-to-human transmission of the COVID-19 as the recent report describing the quick response to COVID-19 in Taiwan by Wang et al. [6]. Table 1 Laboratory-confirmed patients of the 2019 novel coronavirus disease in Taiwan in 16 families (till April 18, 2020). Table 1 Patients Traveling history or contact history Date for confirmed diagnosis Family members (patient number) The period from the first case in the family to the next. Note No. 5 Wuhan City, China January 27, 2020 Husband (No. 8) 5 days No. 8 is the first indigenous patient reported in Taiwan No. 10 Wuhan City, China January 31, 2020 Wife (No. 9) One day No. 14, 15, 17, 18 All traveled to Italy and transited through Hong Kong February, 6, 8, and 9, 2020 Parents and their two sons No. 18 (21 year-old) is the first asymptomatic case reported in Taiwan No. 19 Patient is a taxi driver (taking passengers from China) February, 15, 2020 Younger brother (No. 20), mother (No. 21), nephew-in-law (No.22), sister (No. 23) One days No. 19 is the first death in Taiwan No. 24 Denied (unknown) February, 19, 2020 Granddaughter (No. 25) and daughter (No. 26) 2 days No. 29 Wuhan and Guangzhou City, China February, 24, 2020 Father (No. 27), elder brother (No. 28), mother (No. 30), nephew (No. 31) One day No. 32 (31 year-old) is a foreign temporary caregiver taking care No. 27 No 34 In hospital February 28, 2020 daughter (No. 41), son (No. 46), 3 days No 71 Egypt Mar 17, 2020 Son (No. 92) One day No. 92 (22 year-old) is an asymptomatic case No. 170, 189 All traveled to Spain March 23, 2020 Couple No. 197, 202 All traveled to USA March 24, 2020 Couple No. 172, 173 All traveled to France March 23, 2020 Couple No. 290, 291 All traveled to Indonesia March 29, 2020 Couple No 269 Europe March 28, 2020 Son (No. 299) 2 days No 293 Europe March 29, 2020 Wife (No. 289) 1 days No 356 USA April 3, 2020 Wife (No. 343)Son (5 y/o) (No. 356) 2 days No 356 (60 year-old) is an asymptomatic case No 378, 382 All traveled to Indonesia April 8, 2020April 10, 2020 Couple No 382 (63 year-old) is an asymptomatic case Patient number and data were reported by Taiwan Centers for Disease Control and Taiwan Central Epidemic Command Center (https://www.cdc.gov.tw/En). The familial transmission may also occur before quarantine. Because the family cluster accounted for 50% (17/34) of Taiwanese patients at the end of February 2020, the education for paying more attention both in families and people living together has been launched. With all travelers having to be in-home quarantine after returning to Taiwan since March 19, 2020, in Taiwan [5], it is important to prevent cross-infection between patients and families particularly, also for many countries around the world implementing a global travel ban due to the widespread of the community infection. The major challenges are preventing the families from COVID-19 by the infected individuals who are asymptomatic especially. Another important lesson from Taiwan is the prevention of health care workers including more than 200 thousand foreign caregivers in Taiwan. In addition to from the occupational safety point of view, they are not just employees but also like family due to living together with the family members. With very hard preparation earlier for fighting the COVID-19, the family clusters have to be specially noticed in the near future in Taiwan. Author's contributions Dai CY: Conceptualization; Writing - original draft. Yu ML: Writing - review & editing. Jong YJ: Conceptualization; Supervision; Writing - review & editing. Ho CK: Conceptualization; Supervision; Writing - review & editing; Funding source None. Declaration of competing interest No conflict of interest for all authors.