{Summary)
Main messages
1. This systematic evidence summary (search up 1 May 2026) identified and summarised evidence relating to the incubation and infectious period, asymptomatic or presymptomatic transmission and transmission route in human-to-human transmission of hantavirus infection.
2. Human-to-human transmission was only reported for Andes virus.
3. Seventeen studies were identified to include (1 to 17). All studies were from South America (Argentina, Chile, Paraguay or Uruguay) from 1995 to 2024. Three sets of studies clearly reported on the same outbreak.
4. Seven studies reported the incubation period, or enough information to calculate the incubation period of Andes virus (4, 6, 8, 10, 12, 13, 15, 17). Four of these reported overlapping evidence, (4, 8, 12, 17) leaving 5 independent reports. The reported incubation period ranged from 9 to 40 days, with studies reporting a mean between 21.6 to 27.5 days.
5. Three studies reporting incubation period included children (6, 10, 12). When evidence for children was separated, the range was 14 to 26 days. The mean (and standard deviation, SD) from one study with data to calculate it was 19.8 days (3.7) in children and 21.9 days (7.4) in adults (12). The available evidence was insufficient to determine if there was a significant difference between adults and children and not all studies separated the results.
6. Twelve studies reported the serial interval or enough information to calculate the serial interval of Andes virus (1, 2, 5, 9 to 14, 16, 17). Four of these reported overlapping evidence,(10, 11, 14, 17) leaving 10 independent reports. The reported serial interval ranged from 4 to 40 days with means across studies from 19.6 to 25.7 days.
7. Six studies reporting serial interval included children (2, 5, 9, 10, 12, 16). When evidence for children was separated, the range was 16 to 29 days. The mean (and SD) from one study with data to calculate it was 19.7 (3.5) in children and 19.5 (8.1) in adults. The available evidence was insufficient to determine if there was a significant difference between adults and children and not all studies separated the results.
8. None of the studies reported confirmed route of transmission. Some hypothesised routes from exposures including the possibility of respiratory, direct contact via breastfeeding, other direct contact and sexual transmission. None ruled out respiratory or fomite transmission alongside other possible routes.
9. No studies reported evidence of asymptomatic or presymptomatic transmission.
10. Most studies included groups identified as being at risk of health inequalities, including children, pregnant women, people living in rural settings and people in occupations at higher risk of exposure such as agricultural workers or farmers and people working in healthcare settings. However, none of the studies provided a comparison between groups and it was not possible to determine if outcomes differed in these groups.
11. Critical appraisal was not performed, which restricts the interpretation of the findings, but important limitations have been highlighted. There were a limited number of cases with likely human-to-human transmission which limits the generalisability of the evidence. Many studies also highlighted the possibility than some of these cases also had environmental exposure, although human-to-human transmission was most likely. All studies rely on selfreport of exposure and symptom onset dates, which may be subject to recall bias or misreporting. There was also discrepancy between some studies reporting on the same cases, which highlights the likelihood of misreporting of this evidence.
12. In summary, there was evidence from a limited number of cases to provide information of the incubation period and serial interval for human-to-human transmission of Andes virus. There was no information available that directly informed the infectious period in humans. Evidence suggested incubation period could range from 9 to 40 days, with studies reporting a mean between 21.6 to 27.5 days. The reported serial interval ranged from 4 to 40 days with means from 19.6 to 25.7 days. Although no studies were able to confirm route of transmission, some proposed routes through exposures, including the possibility of direct contact via breast-feeding, and sexual transmission or contact. No studies reported evidence of asymptomatic or presymptomatic transmission. All of the evidence is at risk of bias from misreport or recall bias, possible environmental exposure and ability to generalise due to small numbers of cases.
(...)
Source:
____
No comments:
Post a Comment