Abstract
-
Objectives
This study investigated a cluster of secondary human-to-human transmission of severe fever with thrombocytopenia syndrome (SFTS) in a hospital setting, focusing on infection risk factors and the role of personal protective equipment (PPE).
-
Methods
A descriptive epidemiological investigation was conducted following the death of an index patient with laboratory-confirmed SFTS. A total of 27 close contacts, including healthcare workers and a funeral director, were monitored for symptoms. Suspected cases underwent real-time reverse transcription polymerase chain reaction testing. Clinical features, PPE use, and exposure histories were analyzed. The Fisher exact test was used to assess associations between PPE use and infection. Viral genotyping and sequence analyses were performed to evaluate transmission routes.
-
Results
The index patient deteriorated rapidly and died after repeated cardiopulmonary resuscitation (CPR), during which 8 secondary cases occurred. Most infections were identified among individuals involved in CPR or postmortem care without adequate PPE. Although not statistically significant, infection rates were higher among those who did not wear masks or who used low-filtration masks. Proper use of gloves, gowns, and goggles was associated with lower infection rates. Cycle threshold values in secondary cases (range, 34–39) were higher than in the index case (14.07), suggesting lower viral loads. Sequence analysis demonstrated 99.6%–100% homology between the index and secondary cases; all isolates were genotype B, indicating direct transmission.
-
Conclusion
This study provides molecular and epidemiological evidence of nosocomial SFTS transmission. Inadequate PPE use during aerosol-generating procedures likely facilitated infection, underscoring the importance of strict adherence to PPE protocols and reinforced infection control practices.
-
Keywords: Cross infection; Infection control; Personal protective equipment; Severe fever with thrombocytopenia syndrome
Introduction
Severe fever with thrombocytopenia syndrome (SFTS) is a zoonotic disease caused by SFTS virus (SFTSV), an RNA virus in the genus
Bandavirus and the family
Phenuiviridae. It is transmitted by ticks, including
Haemaphysalis longicornis,
Amblyomma testudinarium,
Ixodes nipponensis, and
Rhipicephalus microplus [
1].
SFTS was first clinically identified in China in 2009 and was officially reported as a novel tick-borne viral disease in 2011. It is now endemic in several regions of China, with SFTSV infection reported in 1%–3% of the population [
2]. Recent studies suggest that Japan may have been the earliest endemic region for SFTSV and that migratory bird routes likely facilitated its initial spread, followed by dissemination throughout East Asia [
3]. Key factors contributing to its spread across East Asia include migratory bird movements and tick-borne transmission among wild animals [
3–
5]. In Japan, the first patient was identified in Yamaguchi Prefecture in the fall of 2012, and numerous cases have since been reported, primarily in western Japan [
6]. In the Republic of Korea, SFTS was designated a Class 4 Notifiable Infectious Disease and has been under surveillance since the first patient was identified in May 2013. Following the 2020 amendment to the Act on the Prevention and Control of Infectious Diseases, it was reclassified as a Class 3 Notifiable Infectious Disease.
The primary route of SFTS transmission is through tick bites. According to a meta-analysis by Woo et al. [
7], tick bites increase the risk of SFTS infection approximately 6-fold. However, person-to-person transmission has also been reported, primarily through contact with blood or body fluids from infected patients [
7]. Furthermore, human infections following contact with SFTS-infected dogs and cats have increasingly been described, representing an additional transmission route [
8,
9]. SFTS can lead to severe complications, including central nervous system involvement, multiple organ failure, and hemophagocytic lymphohistiocytosis [
10–
12]. Delayed diagnosis has been associated with an increased risk of death, whereas high initial viral load and elevated inflammatory markers are associated with progression to severe disease [
13].
Several cases of human-to-human transmission of SFTS have been reported. Among these, exposure to blood or conjunctival secretions has been linked to an increased risk of infection, underscoring the importance of wearing goggles in addition to standard protective equipment [
14]. Some secondary infections have been asymptomatic; others have followed brief contact with blood or secretions from patients with SFTS [
14,
15]. Secondary infections have generally been reported to be clinically milder than primary infections [
16]. Between 1996 and 2019, secondary transmission cases identified in China and the Republic of Korea showed secondary attack rates ranging from 1.72% to 55%, and the basic reproduction number (R0) averaged 0.13 [
16]. In the Republic of Korea, cluster infections have occurred in hospitals treating patients with SFTS, primarily among healthcare workers performing cardiopulmonary resuscitation (CPR) and exposed to blood, body fluids, or contaminated gowns [
17,
18].
This study investigated cases involving healthcare workers and a funeral director who were secondarily infected by a patient who died of SFTS in a healthcare facility. The patient presented in early June 2025 with typical SFTS symptoms, including high fever, thrombocytopenia, and leukopenia. Seven healthcare workers and 1 funeral director were presumed to have been secondarily infected following exposure to blood and body fluids during emergency procedures, including CPR, performed after cardiac arrest during hospitalization. All 8 individuals were laboratory-confirmed to have SFTS. Symptoms, including fever and vomiting, developed between June 17 and June 21. Accordingly, this study analyzed the epidemiological characteristics of these secondary human-to-human SFTS infections and examined the association between personal protective equipment (PPE) use and infection risk to clarify potential transmission patterns.
Materials and Methods
Index Case
The index patient was admitted to Hospital A on June 5, 2025, with pancytopenia of unknown etiology and was transferred to Hospital B on June 9, 2025, because of clinical deterioration.
Her clinical condition subsequently deteriorated, and she was transferred to the intensive care unit around midnight on June 11. She died of multiple organ failure at 9:58 AM on June 11. CPR was performed 5 to 6 times over approximately 5 hours prior to her death, and a total of 22 medical personnel participated in the emergency response. Of these, 9 individuals who developed symptoms, including fever, vomiting, and diarrhea, were tested for SFTS; 7 tested positive. After death, the body was transported from Hospital B to Hospital A for funeral arrangements. Among the 4 funeral directors involved in this process, 1 was confirmed to have SFTS.
The index patient was a woman in her 60s whose initial symptom was fever (maximum temperature, 39.2 °C) beginning on June 2, 2025. She had no history of overseas travel but frequently tended her front garden. The site of the suspected tick bite was unclear, and no eschar was observed. She was admitted to Hospital A on June 5, 2025. At admission, laboratory testing showed a white blood cell (WBC) count of 1.03×10³/μL (reference range, 4.0–10.0×10³/μL) and a platelet count of 86×10³/μL (reference range, 150–450×10³/μL), consistent with leukopenia and thrombocytopenia. After the outbreak was recognized, 1 asymptomatic funeral director who had transported the body was identified as a contact. Subsequently, 4 additional funeral directors who participated in the funeral at Hospital A were traced. One of these individuals presented with fever of unknown origin and thrombocytopenia and was admitted to Hospital B in Cheongju, North Chungcheong Province, where SFTS was confirmed by polymerase chain reaction (PCR) testing on July 1, 2025. In total, 27 individuals were identified as having had contact with the index patient, including 4 at Hospital A and 23 at Hospital B; 8 of these individuals tested positive.
Case Definition
A case was defined as an individual who had close contact with the index patient during high-risk procedures, such as CPR or body handling, and who subsequently developed clinical symptoms consistent with SFTS or had laboratory-confirmed SFTSV infection.
Epidemiological Investigation
A total of 27 contacts were investigated. Among these, 10 individuals at Hospital B who developed symptoms such as fever, myalgia, or gastrointestinal disturbances.
Nine of them underwent testing for SFTSV infection using real-time reverse transcription PCR (RT-PCR), while one refused testing. In addition, 4 funeral directors who handled the body at Hospital A were also tested using RT-PCR. Clinical specimens (serum or throat swabs) were collected, and RT-PCR assays targeting the M and S segments of the SFTSV genome were performed. Cycle threshold (Ct) values for both segments were recorded as indirect indicators of viral load. In addition, epidemiological data—including demographic characteristics, clinical features, exposure sites, and PPE use—were collected for all 27 contacts at Hospitals A and B and were analyzed descriptively.
Statistical Analysis
The infection rate among SFTS contacts and the association between PPE use and infection were analyzed using R ver. 4.4.1 (R Foundation for Statistical Computing). For each type of PPE (gloves, gown, mask, and goggles/face shield), the infection rate was calculated as the proportion of confirmed cases among individuals who used that specific PPE. Infection rate distributions by type of PPE were visualized using the ggplot2 package. The Fisher exact test was used to compare infection rates according to PPE use, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.
Laboratory Analysis
Nine positive serum samples, including that of the index patient, were collected from this SFTS cluster and subjected to SFTSV genotyping and sequence homology analysis.
Ethics Statement
This study was approved by the Institutional Review Board (IRB) of the Korea Disease Control and Prevention Agency (IRB No: 2025-08-03-PE-01).
Results
Clinical Characteristics
The index patient developed symptoms on June 2, was admitted to Hospital A on June 5, and was transferred to Hospital B on June 9.
Due to clinical deterioration, she was transferred to the intensive care unit on June 11. Despite repeated CPR, she died later that day. A total of 27 individuals were identified as having had contact with the patient before or after her death. Of these, 13 developed symptoms suggestive of SFTS and underwent real-time RT-PCR testing. Eight healthcare workers and funeral directors involved in patient care or body handling were confirmed to have contracted the virus (
Figure 1).
Between 5:00 AM and 10:00 AM on June 11, 2025, CPR was performed 5 to 6 times, including central venous catheter insertion, urinary catheter placement, endotracheal intubation, and mechanical ventilation. Repeated sputum suctioning and manual ventilation using an Ambu bag were performed, and blood was observed in the endotracheal tube. Sputum suctioning generated large amounts of bloody secretions, which likely increased the risk of skin and mucosal exposure. In addition, substantial aerosol generation likely occurred during manual ventilation, creating a high-risk exposure environment for healthcare workers.
All secondary cases developed symptoms between June 17 and June 21 and shared a history of high-risk exposure (e.g., CPR, contact with blood or body fluids, and body handling) around the time of the index patient’s death. The 8 confirmed cases included 2 physicians, 5 nurses, and 1 funeral director (
Figure 1). None reported a history of tick bites, and the epidemiological findings strongly supported human-to-human transmission. These observations suggest that close contact with blood and body fluids during CPR was a major factor associated with increased SFTS transmission risk. Specifically, improper or inconsistent PPE use during emergency treatment or postmortem care likely contributed to infection.
The index patient exhibited marked leukopenia (WBC, 3.27×10³/μL) and thrombocytopenia (platelet count [PLT], 27×10³/μL), with an absolute neutrophil count of 2.13×10³/μL (reference range, 1.5–8.0×10³/μL). Liver enzyme levels were markedly elevated, with aspartate aminotransferase (AST) at 3,040 IU/L (reference range, 10–40 IU/L); lactate dehydrogenase (LDH) was also high at 24,690 IU/L (reference range, 140–280 IU/L). High-sensitivity C-reactive protein was mildly elevated at 0.55 mg/dL (<1.0 mg/dL, low risk). The Ct value for the M segment on RT-PCR was 14.07, indicating a high viral load.
In contrast, the 8 confirmed secondary cases showed mild decreases in WBC and PLT along with modest elevations in AST and LDH, although these abnormalities were less pronounced than in the index patient. The M segment Ct values ranged from 34 to 39, indicating markedly higher Ct values—and therefore lower viral loads—than in the index patient. The index patient was 69 years old, whereas the secondary cases were younger, with a median age of 34 years (range, 26–55 years). The demographic and clinical characteristics of the index and secondary cases are summarized in
Table 1.
Wearing PPE
To examine the association between PPE use and secondary SFTS infection, the 27 close contacts were categorized according to PPE use. Mask type was classified into 4 categories: no mask, dental mask, KF94 mask, and N95 respirator. Individuals who did not wear masks or who wore lower-filtration masks tended to have higher infection rates.
Specifically, the odds of SFTS infection were higher among individuals who did not wear masks compared with those who wore higher-grade masks (OR, 4.80; 95% CI, 0.62–36.8). Similarly, individuals who did not use eye protection had higher odds of infection than those who did (OR, 5.20; 95% CI, 0.57–47.2). However, the CIs were wide and included 1, reflecting statistical uncertainty due to the small sample size.
No statistically significant association was observed between PPE type and SFTS infection (
p>0.05). Nevertheless, infections occurred more frequently among individuals who did not wear masks or gloves properly (
Table 2;
Figure 2). Individual-level exposure characteristics, procedures performed, and PPE use are summarized in
Table S1 for all 27 contacts, with stratified presentation for infected and non-infected individuals. Aggregate-level comparisons are shown in
Table 2.
Genotypic Characterization
Five of the 8 specimens from the index patient and secondary cases were successfully genotyped, and all were classified as genotype B. Genotype B showed strong similarity to SFTSV strains previously reported in the Republic of Korea, indicating that these secondary infections were not imported but were instead caused by a locally circulating strain. Furthermore, the homology of the SFTSV S segment between the index case and 4 contacts was high, ranging from 99.6% to 100%, supporting a common source of infection. The remaining 3 cases had low viral loads and could not be analyzed (
Table 3).
Discussion
In this study, 8 of 27 contacts who were directly or indirectly involved in medical procedures or postmortem handling of a patient with SFTS were confirmed to have secondary infection. None of the infected individuals reported a history of tick bites, and their shared involvement in high-risk clinical or postmortem procedures with the index patient strongly supports human-to-human transmission.
The 8 infected individuals included 2 physicians, 5 nurses, and 1 funeral director who participated in invasive procedures such as CPR, endotracheal intubation, central venous catheter insertion, sputum suctioning, and manual ventilation before and after the index patient’s death. The presence of bloody sputum and likely aerosol generation during CPR created an environment with a high risk for virus transmission. The index patient exhibited a severe clinical course, characterized by markedly elevated liver enzymes (AST, 3,040 IU/L; alanine aminotransferase, 510 IU/L), elevated LDH (24,690 IU/L), and thrombocytopenia (PLT, 27×10³/μL). These findings are consistent with previous research [
19] indicating that severe SFTS is associated with liver dysfunction, thrombocytopenia, and elevated tissue injury markers such as LDH.
In contrast, most secondary SFTS cases presented with mild to moderate clinical manifestations. Laboratory findings showed relatively preserved PLT and lower levels of liver injury markers. Viral load also differed substantially from that of the index patient. The index patient had a markedly low Ct value (M segment, 14.07), whereas secondary cases had substantially higher Ct values (34.65–38.96), consistent with lower viral loads. These findings suggest that transmission likely occurred during high-risk procedures performed when the index patient had a high viral burden. However, the viral load detected in secondary cases was considerably lower.
To evaluate the effectiveness of PPE in preventing infection, the 27 contacts were surveyed regarding the use of 4 types of PPE: masks, gloves, gowns, and goggles/face shields. Regarding masks, infection rates were highest among individuals who did not wear masks (50%) or who wore dental masks (36.4%). In contrast, infection rates were lower among those wearing KF94 masks (11.1%) and absent among those wearing N95 respirators (0%)—both mask types known for higher filtration efficiency—indicating a clear protective effect. Similar patterns were observed for gloves, gowns, and eye protection, with higher infection rates among those who did not use PPE.
The Fisher exact test was performed to assess differences in infection rates across PPE types. No significant differences were observed, likely due to the limited sample size (n=27). Nonetheless, the 8 individuals who became infected either did not wear PPE or did not use it appropriately. Visual inspection of the results showed a consistent pattern of higher infection rates among those who did not wear PPE. Notably, the observed ORs were substantial, particularly for mask use (OR, 4.80) and eye protection (OR, 5.20). However, the CIs were wide and included 1, indicating considerable uncertainty around these estimates. Although based on a limited sample, these findings suggest that PPE may help prevent secondary human-to-human transmission and plays an important role in infection control. Furthermore, during prolonged emergency procedures such as CPR, large amounts of blood, droplets, and aerosols can be generated; in such situations, appropriate PPE use is especially critical to reduce infection risk.
Some individuals diagnosed with SFTS were found to have come into direct contact with the index patient without wearing gloves and gowns. Goggles and face shields, among other protective equipment, play a crucial role in preventing the spread of droplets and blood from the infected person to the facial mucosa. However, their use was inadequate in most cases.
Genotyping of 5 samples from the index patient and secondary cases identified genotype B, the predominant strain in the Republic of Korea. The S segment homology between the index and secondary cases was very high (99.6%–100%), suggesting the presence of identical viral strains and further supporting direct transmission from the index patient.
High-risk emergency procedures performed in medical facilities, such as CPR and endotracheal intubation, may increase the likelihood of person-to-person SFTSV transmission through exposure to blood, body fluids, and aerosols. In these settings, strict adherence to PPE protocols represents an effective measure for reducing infection risk. In addition to standard precautions for infection prevention, enhanced individual protection measures, including contact, droplet, and airborne precautions, are essential.
However, during urgent situations such as CPR, immediate patient care may limit adherence to recommended PPE protocols. In this cluster, many infected individuals were healthcare workers directly or indirectly involved in treating the index patient, as confirmed in this case, suggesting that PPE use may not have been feasible. Nevertheless, when managing patients with suspected or confirmed SFTS, infection risk should be considered at the outset. Appropriate PPE use and thorough decontamination before and after procedures are critical to reducing transmission risk. Given the elevated transmission risk during emergency interventions, systematic reinforcement of infection control protocols and PPE adherence within healthcare facilities is necessary.
The absence of funeral directors from Hospital A among the initially identified close contacts appears to reflect structural limitations in inter-institutional coordination rather than deficiencies in individual exposure assessment. At the time of this event, transfer of the deceased relied on informal communication rather than a standardized inter-hospital coordination system, which delayed identification, tracing, and exposure assessment of funeral personnel during the early investigation phase.
This case highlights a potential gap in infection control and epidemiological investigation systems, whereby postmortem transfer and funeral-related activities occurring outside healthcare facilities may not be fully captured. These findings underscore the need for clearer inter-institutional coordination mechanisms and defined responsibilities to ensure appropriate identification and protection of funeral personnel who may be occupationally exposed.
Funeral directors represent a high-risk occupational group due to the nature of their work. During body handling, mucosal contact with blood or body fluids, inhalation of aerosolized material, and direct pathogen exposure may facilitate transmission [
20]. In SFTS cases, although excreta such as vomitus or stool from patients without bleeding are generally considered to pose a lower transmission risk than blood [
21], the infection observed in a funeral director in this study demonstrates that transmission can occur during postmortem handling. Strict infection control measures are therefore essential during funeral and mortuary procedures involving patients with SFTS.
Limitations
This study analyzed secondary infections arising from a single medical institution and included 27 contacts. This limited sample size may have contributed to the lack of statistically significant findings.
PPE use and exposure information were collected retrospectively through surveys and record review, introducing the potential for recall bias and incomplete data. Furthermore, PPE adherence was determined primarily by self-report or indirect confirmation. Any resulting misclassification is likely to have been non-differential between infected and non-infected individuals, which would bias effect estimates toward the null and potentially underestimate the true effect of PPE use.
The precise timing and degree of exposure among secondary cases could not be determined, limiting the ability to quantify the protective effect of PPE.
Ct values were used as indirect indicators of viral concentration; however, comparisons are limited by potential variability in exposure timing and viral load. In addition, low viral concentrations in some secondary cases precluded genotyping and limited verification of genetic concordance among all confirmed cases.
Conclusion
This study provides evidence supporting the protective effects of PPE in a case of human-to-human transmission of SFTS within a healthcare facility. Failure to wear appropriate PPE was associated with increased infection risk, with mask use appearing particularly important. Strict adherence to standardized PPE protocols is essential during high-risk emergency procedures, and systematic infection prevention measures should also be implemented during postmortem care for patients who have died from SFTS.
HIGHLIGHTS
• We analyzed a cluster of secondary human-to-human transmission of severe fever with thrombocytopenia syndrome involving 8 healthcare workers following high-risk procedures, including cardiopulmonary resuscitation.
• Inadequate or absent use of personal protective equipment, especially low-filtration masks, was associated with an increased risk of infection, although statistical significance was limited by the small sample size.
• Viral sequencing identified genotype B with 99.6%–100% homology between the index and secondary cases, providing molecular evidence of direct nosocomial transmission and emphasizing the urgent need for strengthened infection control measures.
Article information
Ethics Approval
This study was approved by the Institutional Review Board of the Korea Disease Control and Prevention Agency (KDCA) (IRB No. 2025-08-03-PE-01).
Conflicts of Interest
The authors have no conflicts of interest to declare.
Availability of Data
All data generated or analyzed during this study are included in this published article.
Authors’ Contributions
Conceptualization: SP, YK; Data curation: SP; Formal analysis: SP; Investigation: SP, HYL; Methodology: SP, HYL; Project administration: SP, JK; Resources: SP; Software: SP; Supervision: HYL, YK; Validation: HYL, JK, YK; Visualization: SP, HYL; Writing–original draft: SP, HYL; Writing–review & editing: all authors. All authors read and approved the final manuscript.
Acknowledgements
We gratefully acknowledge the medical professionals at the participating hospital for their assistance in providing clinical information and for their cooperation throughout the study.
Supplementary Material
Figure 1.Epidemic curve and transmission linkage of the index case and 8 secondary human severe fever with thrombocytopenia syndrome infections.
Figure 2.Infection rates according to personal protective equipment usage among close contacts of the severe fever with thrombocytopenia syndrome index case. Infection rate by (A) mask type, (B) glove use, (C) gown use, and (D) goggle/face shield use.
Table 1.Demographic and clinical-epidemiological characteristics of the index case and secondary SFTS infections
Table 1.
| Characteristic |
Index case |
Patient #1 |
Patient #2 |
Patient #3 |
Patient #4 |
Patient #5 |
Patient #6 |
Patient #7 |
Patient #8 |
| Sex |
Female |
Female |
Male |
Male |
Female |
Female |
Male |
Female |
Male |
| Age (y) |
69 |
26 |
30 |
29 |
49 |
28 |
38 |
40 |
55 |
| Occupation |
Unemployed |
Nurse |
Nurse |
Nurse |
Doctor |
Nurse |
Doctor |
Nurse |
Funeral director |
| Date of onset |
June 2, 2025 |
June 17, 2025 |
June 17, 2025 |
June 17, 2025 |
June 17, 2025 |
June 18, 2025 |
June 19, 2025 |
June 20, 2025 |
June 21, 2025 |
| Temperature (°C) |
39.2 |
38.0 |
38.1 |
39.3 |
38.0 |
38.0 |
38.0 |
38.0 |
37.7 |
| Clinical symptoms |
Fever |
Fever, myalgia |
Fever, headache |
Fever, myalgia |
Fever, myalgia, rash |
Fever, myalgia |
Fever, diarrhea |
Fever, myalgia |
Fever, chills, myalgia, vomiting |
| Underlying disease |
No |
VPB |
Hyperlipidemia |
Gout, kidney donor |
IDA, carcinoma of the uterine cervix, Tis |
No |
No |
Asthma |
No |
| WBC (CBC) (×103/μL) |
3.27 |
2.79 |
3.06 |
2.23 |
1.76 |
2.00 |
4.49 |
2.05 |
1.61 |
| PLT (×103/μL) |
27 |
126 |
151 |
155 |
108 |
135 |
155 |
160 |
60 |
| ANC (×103/μL) |
2.13 |
2.05 |
1.65 |
1.01 |
1.17 |
1.28 |
0.69 |
1.11 |
1.11 |
| Creatinine (mg/dL) |
0.70 |
0.73 |
1.33 |
0.89 |
0.57 |
0.67 |
0.99 |
0.50 |
1.09 |
| AST (IU/L ) |
3,040 |
21 |
25 |
28 |
34 |
58 |
47 |
26 |
179 |
| ALT (IU/L ) |
510 |
13 |
20 |
18 |
25 |
69 |
54 |
20 |
85 |
| hs-CRP (mg/dL) |
0.55 |
0.22 |
0.14 |
0.07 |
0.28 |
0.07 |
0.08 |
0.04 |
- |
| LDH (serum) (IU/L ) |
24,690 |
366 |
375 |
492 |
307 |
309 |
600 |
643 |
- |
| PT (INR) |
1.48 |
1.04 |
1.07 |
1.01 |
0.96 |
0.99 |
0.97 |
1.03 |
1.00 |
| Ct (M segment) |
14.07 |
37.59 |
38.96 |
37.78 |
34.79 |
34.65 |
35.48 |
36.6 |
34.86 |
| Ct (S segment) |
12.87 |
38.94 |
38.45 |
35.95 |
34.5 |
33.62 |
35.11 |
37.48 |
35.45 |
| Outcome |
Death |
Discharge |
Discharge |
Admitted and discharged |
Discharge |
Discharge |
Admitted and discharged |
Discharge |
Discharge |
Table 2.Association between personal protective equipment usage and infection status: results of the Fisher exact test
Table 2.
| PPE |
Negative (n=19) |
Positive (n=8) |
OR (95% CI) |
pa)
|
| Gloves |
|
|
2.14 (0.32–14.7) |
0.6 |
| Not worn |
4 (21.1) |
3 (37.5) |
|
|
| Worn |
15 (78.9) |
5 (62.5) |
|
|
| Gown |
|
|
1.70 (0.30–9.65) |
0.7 |
| Not worn |
7 (36.8) |
4 (50.0) |
|
|
| Worn |
12 (63.2) |
4 (50.0) |
|
|
| Mask |
|
|
4.80 (0.62–36.8) |
0.3 |
| Not worn |
3 (15.8) |
3 (37.5) |
|
|
| Dental |
7 (36.8) |
4 (50.0) |
|
|
| KF94 |
8 (42.1) |
1 (12.5) |
|
|
| N95 |
1 (5.3) |
0 (0) |
|
|
| Goggles/face shield |
|
|
5.20 (0.57–47.2) |
>0.9 |
| Not worn |
15 (78.9) |
7 (87.5) |
|
|
| Worn |
4 (21.1) |
1 (12.5) |
|
|
Table 3.Genotypic analysis of SFTSV using conventional RT-PCR and sequence identity with the index case
Table 3.
|
Conventional RT-PCR |
Nucleotide sequence identitya) (%) |
| L (483 bp) |
M (560 bp) |
S (567 bp) |
L |
M |
S |
| Index case |
Amplified |
Amplified |
Amplified |
|
| #1 |
- |
- |
Amplified |
- |
- |
100 |
| #2 |
- |
- |
| #3 |
- |
Amplified |
- |
- |
100 |
- |
| #4 |
Amplified |
- |
Amplified |
100 |
- |
99.6 |
| #5 |
- |
Amplified |
Amplified |
- |
100 |
100 |
| #6 |
- |
- |
Amplified |
- |
- |
100 |
| #7 |
- |
- |
| #8 |
- |
- |
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