Explore the vast range of titles available.

Human adenovirus type 55 (HAdV-55) causes acute respiratory disease of variable severity and has become an emergent threat in both civilian and military populations. HAdV-55 infection is endemic to China and South Korea, but data from other regions and time periods are needed for comprehensive assessment of HAdV-55 prevalence from a global perspective. In this study, we subjected HAdV-55 isolates from various countries collected during 1969-2018 to whole-genome sequencing, genomic and proteomic comparison, and phylogenetic analyses. The results show worldwide distribution of HAdV-55; recent strains share a high degree of genomic homogeneity. Distinct strains circulated regionally for several years, suggesting persistent local transmission. Several cases of sporadic introduction of certain strains to other countries were documented. Among the identified amino acid mutations distinguishing HAdV-55 strains, some have potential impact on essential viral functions and may affect infectivity and transmission.

Human adenoviruses (AdV) are mostly associated with minimal pathology. However, more severe respiratory tract infections and acute respiratory diseases, most often caused by AdV-4 and AdV-7, have been reported. The only licensed vaccine in the United States, live oral AdV-4 and AdV-7 vaccine, is indicated for use in the military, nearly exclusively in recruit populations. The excellent safety profile and prominent antibody response of the vaccine is well established by placebo-controlled clinical trials, while, long-term immunity of vaccination has not been studied. Serum samples collected over 6 years from subjects co-administered live oral AdV-4 and AdV-7 vaccine in 2011 were evaluated to determine the duration of the antibody response. Group geometric mean titers (GMT) at 6 years post vaccination compared to previous years evaluated were not significantly different for either AdV-4 or AdV-7 vaccine components. There were no subjects that demonstrated waning neutralization antibody (NAb) titers against AdV-4 and less than 5% of subjects against AdV-7. Interestingly, there were subjects that had a four-fold increase in NAb titers against either AdV-4 or AdV-7, at various time points post vaccination, suggesting either homotypic or heterotypic re-exposure. This investigation provided strong evidence that the live oral AdV-4 and AdV-7 vaccine induced long-term immunity to protect from AdV-4 and AdV-7 infections.

Background Vesiviruses (family Caliciviridae ) had been shown capable of invading a variety of host species, raising concern of their zoonotic potential. Since the 1980’s, several canine caliciviruses (CaCV) isolates have been reported and are phylogenetically related to the vesiviruses with features distinct from both Vesicular exanthema of swine virus (VESV) and Feline calicivirus (FCV) species in phylogeny, serology and cell culture specificities. Etiological studies of canine diseases in dogs used for military services and laboratory studies were conducted in 1963–1978 at the Walter Reed Army Institute of Research. Multiple known and unknown viral pathogens including caliciviruses were recovered. Methods Four unidentified isolates were recovered in Walter Reed Canine Cells (WRCC) from respiratory, fecal and penile specimens. Physicochemical tests, electron microscopy, viral cultivation in human and animal cells, antibody neutralization assays, and recently the genome sequencing were used to characterize the isolates. Sera from these dogs and their cohorts were tested with the isolates to determine origin and prevalence of the infections. Results The viral isolates were small non-enveloped spherical RNA virions, 27 to 42 nm in diameter with cup-like structures, indicating they are caliciviruses. They propagated in WRCC and MDCK cells, not in either other canine cells or human and other animal cells. Each isolate is antigenically distinct and react with dog sera in respective cohorts. The genomes have nucleotide identities ranging from 70.3% to 90.7% and encode the non-structural polyprotein (1810 amino acids), major capsid protein (691 amino acids) and minor structural protein (134 amino acids). They belong to two different phylogenetic clades in Vesivirus genus with close relation with canine calicivirus (CaCV). Conclusions These CaCV isolates have restricted cell tropism, antigenic diversity and genetic variation. Further investigation will shed light on antigenic relation to other vesiviruses, and its pathogenicity for dogs and potential infectivity to other animals. Together with the previously reported CaCV strains provides significant evidence to support the formation of a new CaCV species in the Vesivirus genus.

Outbreaks of adenovirus type 4 (Ad4) acute respiratory disease (ARD) have reemerged among US military personnel during the past decade. A prospective epidemiological investigation of 678 military recruits was conducted at Fort Jackson, South Carolina, in the fall of 1998; 115 (17%) of the recruits were hospitalized for febrile ARD. Adenovirus types 4, 3, and 21 were recovered from the cultures of 70 (72%), 7 (7%), and 2 (2%) of 97 recruits, respectively. In addition, 69 (83%) of the 83 hospitalized and 82 (49%) of the 166 nonhospitalized unit contacts had seroconversion to Ad4, which indicates the very high susceptibility and communicability of Ad4 among military recruits. Young age (<20 years) and male sex increased the risk for anti-Ad4 seroconversion. Recruits from tropical areas had higher preexisting immunity than did recruits from temperate regions. Military recruits are highly susceptible to Ad4 infections. Prompt reinstitution of an adenovirus vaccination program in this high-risk population is urgently needed.

ABSTRACT A candidate new canine picornavirus was isolated from a respiratory swab collected from an American foxhound (Canis lupus familiaris) in 1968. The assembled genome sequence of strain A128thr is 7,618 bases in length, comprising a complete protein-coding sequence of the 2,213-amino-acid polyprotein and partial terminal untranslated sequences.

Acute respiratory disease (ARD) due to adenoviruses is a reemerging disease in military recruits. It is a challenge for clinicians to accurately diagnose this disease and to appropriately treat affected individuals. This study investigated the utility of a quantitative, rapid-cycle, real-time fluorogenic polymerase chain reaction (PCR) technique for detecting adenovirus type 4 (Ad4) in a clinical setting. Throat swab specimens and clinical data were collected from US Army basic trainees hospitalized with ARD at Fort Jackson, South Carolina. A total of 140 throat swab specimens were collected from 83 subjects. Rapid PCR results (obtained in <2 h) had a sensitivity of 100% and a specificity of 100%, compared with viral culture. There was no difference, qualitative or quantitative, between frozen and fresh samples for PCR detection of Ad4. Individuals with test results positive for Ad4 were hospitalized longer than were individuals with negative test results. Higher virus loads at hospital admission corresponded to longer lengths of stay for Ad4-positive subjects.

Adenovirus-associated acute respiratory disease (AARD) is well documented in the U.S. military, but little information is readily available on its occurrence in other healthy populations that might also benefit from adenovirus vaccines. We reviewed publications on AARD in non-U.S. military,immunocompetent, young adults in group-living settings. Since adenovirus disease can be severe in immunocompromised and pediatric patients, we also considered AARD in healthcare workers. We evaluated 83 publications, published between 1950 and 2005, concerning 22 countries. Most described outbreaks in foreign military recruits and were published before 1970. More recent reports documented outbreaks in student dormitories and medical facilities. The 83 reports did not provide evidence for AARD being a serious, persistent, contemporary concern in the populations studied, nor did they identify strong interest in adenovirus vaccines. Currently availability, sensitive, molecular diagnostic tests may better define the importance of AARD in populations outside the U.S. military.