We investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination in 2 rooms of a quarantine hotel after 2 presymptomatic persons who stayed there were ...laboratory-confirmed as having coronavirus disease. We detected SARS-CoV-2 RNA on 8 (36%) of 22 surfaces, as well as on the pillow cover, sheet, and duvet cover.
Serum samples from patients convalescing after SARS-CoV-2 infection and after vaccination with BBIBP-CorV or CoronaVac in China neutralized pseudoviruses expressing spike proteins from the B.1.1.7 ...variant at levels that were similar to those from the wild-type (Wuhan) isolate but lower than those from the B.1.351 variant.
Abstract
Background
The duration of humoral and T and B cell response after the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains unclear.
Methods
We performed a ...cross-sectional study to assess the virus-specific antibody and memory T and B cell responses in coronavirus disease 2019 (COVID-19) patients up to 343 days after infection. Neutralizing antibodies and antibodies against the receptor-binding domain, spike, and nucleoprotein of SARS-CoV-2 were measured. Virus-specific memory T and B cell responses were analyzed.
Results
We enrolled 59 patients with COVID-19, including 38 moderate, 16 mild, and 5 asymptomatic patients; 31 (52.5%) were men and 28 (47.5%) were women. The median age was 41 years (interquartile range, 30–55). The median day from symptom onset to enrollment was 317 days (range 257 to 343 days). We found that approximately 90% of patients still have detectable immunoglobulin (Ig)G antibodies against spike and nucleocapsid proteins and neutralizing antibodies against pseudovirus, whereas ~60% of patients had detectable IgG antibodies against receptor-binding domain and surrogate virus-neutralizing antibodies. The SARS-CoV-2-specific IgG+ memory B cell and interferon-γ-secreting T cell responses were detectable in more than 70% of patients.
Conclusions
Severe acute respiratory syndrome coronavirus 2-specific immune memory response persists in most patients approximately 1 year after infection, which provides a promising sign for prevention from reinfection and vaccination strategy.
SARS-CoV-2-specific antibody and memory T and B cell responses were detectable in most patients approximately 1 year after infection, indicating that durable immunity against secondary COVID-19 disease is possible in most individuals.
Summary Since the beginning of the 1980s, 33 emerging tick-borne agents have been identified in mainland China, including eight species of spotted fever group rickettsiae, seven species in the family ...Anaplasmataceae, six genospecies in the complex Borrelia burgdorferi sensu lato, 11 species of Babesia , and the virus causing severe fever with thrombocytopenia syndrome. In this Review we have mapped the geographical distributions of human cases of infection. 15 of the 33 emerging tick-borne agents have been reported to cause human disease, and their clinical characteristics have been described. The non-specific clinical manifestations caused by tick-borne pathogens present a major diagnostic challenge and most physicians are unfamiliar with the many tick-borne diseases that present with non-specific symptoms in the early stages of the illness. Advances in and application of modern molecular techniques should help with identification of emerging tick-borne pathogens and improve laboratory diagnosis of human infections. We expect that more novel tick-borne infections in ticks and animals will be identified and additional emerging tick-borne diseases in human beings will be discovered.
The dynamics, duration, and nature of immunity produced during SARS-CoV-2 infection are still unclear. Here, we longitudinally measured virus-neutralising antibody, specific antibodies against the ...spike (S) protein, receptor-binding domain (RBD), and the nucleoprotein (N) of SARS-CoV-2, as well as T cell responses, in 25 SARS-CoV-2-infected patients up to 121 days post-symptom onset (PSO). All patients seroconvert for IgG against N, S, or RBD, as well as IgM against RBD, and produce neutralising antibodies (NAb) by 14 days PSO, with the peak levels attained by 15-30 days PSO. Anti-SARS-CoV-2 IgG and NAb remain detectable and relatively stable 3-4 months PSO, whereas IgM antibody rapidly decay. Approximately 65% of patients have detectable SARS-CoV-2-specific CD4
or CD8
T cell responses 3-4 months PSO. Our results thus provide critical evidence that IgG, NAb, and T cell responses persist in the majority of patients for at least 3-4 months after infection.
The BA.1, BA.2, and BA.3 omicron subvariants of SARS-CoV-2 showed similar but substantial resistance to vaccine-induced and infection-induced serum neutralising activity.1,2 The new BA.2.12.1, ...BA.2.13, BA.4, and BA.5 omicron subvariants containing Leu452 substitutions show more infectious potential than BA.2.3 We examined neutralising activity against the BA.1, BA.2, BA.2.11, BA.2.12.1, BA.2.13, BA.4, and BA.5 omicron subvariants in serum from people who received BBIBP-CorV (Sinopharm) primary immunisation, people who received BBIBP-CorV or ZF2001 (Anhui Zhifei Longcom) boosters, and people with omicron breakthrough infections (appendix pp 4, 7). Using an in-house pseudovirus neutralisation assay we found that two BBIBP-CorV doses induced detectable neutralising antibodies against spike protein mutation D614G in 21 (84%) individuals, but neutralising activity against omicron subvariants (BA.1, BA.2, BA.2.11, BA.2.12.1, BA.2.13, and BA.4/BA.5) was not or only minimally detectable (appendix pp 2–3, 8). Neutralising activity against omicron subvariants was observed in 24–48% of people who received a BBIBP-CorV booster and 30–53% of people who received a ZF2001 booster (appendix pp 2–3, 9). ...serum samples with neutralising antibody titres higher than the limit of detection (limit of detection was 30) against the omicron subvariants had lower neutralising activity, with a 4·6–17·1-times lower GMT than the GMT against D614G (appendix pp 2–3).
Additionally, BA.1, BA.2, BA.4/5, and BF.7 exhibited susceptibility to BA.2.76 breakthrough infection serum samples; however, BA.2.75 showed more resistance than BA.2 and BA.4/5 (figure E). ......BA.2.75 is more resistant to breakthrough BF.7 infection neutralisation than BA.2 and BA.4/5. ...comparisons showed that BA.5.1.2 breakthrough infections induced a broader antibody response against the tested subvariants and induced significantly higher geometric mean titres against BQ.1 and BQ.1.1 compared with delta, BA.1, BA.2.2, BA.2.76, or BF.7 breakthrough infections (figure; appendix p 7). Omicron subvariants BQ.1 and BQ.1.1 with increased resistance to neutralising antibodies can pose a challenge to immunity induced by vaccination or infection and render therapeutic monoclonal antibodies ineffective.3–6 Our results suggest that BQ.1 and BQ.1.1 extensively, but incompletely, escape omicron subvariant breakthrough infection neutralisation, including the most recent BA.5.1.2, BA.2.76, and BF.7 infections.
Novel highly pathogenic avian influenza (HPAI) H7N9 viruses of the fifth epidemic wave infect humans and poultry. Recently, HPAI H7N9 viruses have evolved into different subtypes and genotypes, ...exhibited heightened virulence in mammals, and extended their host range, thereby posing a potential threat to public health and the poultry industry.
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