BACKGROUND/AIMS: Parthenolide is a sesquiterpene lactone that is present in plants of the Tanacetum genus, for which many biological effects have already been reported, including antiherpetic activity. Although the effec...BACKGROUND/AIMS: Parthenolide is a sesquiterpene lactone that is present in plants of the Tanacetum genus, for which many biological effects have already been reported, including antiherpetic activity. Although the effectiveness of parthenolide against Herpes simplex virus 1 (HSV-1) has already been demonstrated, such findings are still controversial. The objective of this study was to investigate the ways in which parthenolide exerts anti-HSV-1 activity. METHODS: The cytotoxicity and antiviral activity of parthenolide were determined by the MTT method and plaque reduction assay, respectively. The expression of cell and viral proteins during the treatment of infected cells was investigated by Western blot. RESULTS: Both strains of HSV-1 were sensitive to parthenolide, and parthenolide was active only after penetration of the virus into the host cell. The expression of p65 protein decreased, the expression of caspases 8 and 9 increased, and the expression of c-Jun N-terminal kinase (JNK) and p38 protein was altered in infected cells after parthenolide treatment, resulting in lower cell survival. The low expression of viral proteins gB, gD, and ICP0 confirmed the reduction of HSV-1 particle production. CONCLUSION: Parthenolide exerts anti-HSV-1 activity by impairing cell viability, which consequently interferes with the efficient infection and production of new viral particles.
According to the latest update, 2,578 unique mature micro-RNAs (miRNAs) are currently annotated in the human genome and participate in the regulation of multiple events, such as cellular proliferation or apoptosis. A pre...According to the latest update, 2,578 unique mature micro-RNAs (miRNAs) are currently annotated in the human genome and participate in the regulation of multiple events, such as cellular proliferation or apoptosis. A previous study analyzing global miRNA expression patterns in GH cells (high human endogenous retrovirus, HERV, K vs. low) showed that 2 miRNAs (miR-663 and miR-638) are differentially regulated and exhibit expression parallel to that of HERV-K. The aim of this study was to evaluate HERV-K and -W pol gene and miR-155 expression in kidney transplant recipients and the possible relationship between them. The comparison between kidney transplant patients negative for human cytomegalovirus (HCMV) infection and positive patients showed a significant difference in terms of miR-155 expression (p = 0.0111). We demonstrated that HERV-K and -W pol gene expression was significantly higher in CMV-infected kidney transplant recipients versus those not infected as previously reported by our groups. Our correlation data suggest that miR-155 are not directly involved in regulating the HERV notwithstanding that we together observed increased expression of HERV-K and -W and diminished expression of miR-155 in HCMV-infected human kidney transplant recipients.
Group A rotavirus (RVA) is a serious public problem in China, with a prevalence of 29.7% in diarrhea cases under 5 years of age. A total of 1,224 fecal specimens were collected in 2015 from children under 5 years of age...Group A rotavirus (RVA) is a serious public problem in China, with a prevalence of 29.7% in diarrhea cases under 5 years of age. A total of 1,224 fecal specimens were collected in 2015 from children under 5 years of age with acute gastroenteritis in Kunming, China, for detection and characterization of rotavirus. The prevalence of RVA was 28.5%. The frequency of RVA detection was greatest (52%) among children aged 7-12 months. The following strains were the most common types: G9P(8) (58.2%), G3P(8) (14.9%), and G1P(8) (6.9%). The following strains were uncommon types: G3P(4), G8P(9), and G9P(4) (1.1%); G1P(4), G2P(8), and G4P(8) (0.9%); G2P(6), G3P(9), G4P(6), and G9P(6) (0.6%); and G4P(4) (0.3%). G3G1P(8) (5.2%), G1G2P(4) (0.9%), G1G9P(8) (0.6%), and G2P(4)P(8) (0.3%) were mixed types. This study documents the molecular epidemiology, genetics, and diversity of rotavirus strains in children under 5 years of age in Kunming, China, and suggests that it may be important to offer RVA vaccination and scientific evidence to stop and control RVA-related diarrhea.
AIM: The study was designed to identify putative Chikungunya virus (CHIKV) receptor/s on C6/36 cells that facilitate viral entry. METHODS: The virus overlay protein binding assay (VOPBA) was adopted to identify CHIKV-int...AIM: The study was designed to identify putative Chikungunya virus (CHIKV) receptor/s on C6/36 cells that facilitate viral entry. METHODS: The virus overlay protein binding assay (VOPBA) was adopted to identify CHIKV-interacting bands present in C6/36 cell membrane and identity of the protein was established by mass spectrometry. The role of this protein as a putative CHIKV receptor on C6/36 cells was confirmed by infection inhibition assay. Cell surface localization of the identified protein was studied by indirect immunofluorescence assay (IFA) on nonpermeabilized cells and by flow cytometry. Interaction between this protein and CHIKV was confirmed by co-immunoprecipation (Co-IP) and Western blotting. The effect of depletion of the identified protein by quercetin was demonstrated by infection inhibition assay. RESULTS: A 70-kDa protein was identified as a CHIKV-interacting protein by VOPBA. MALDI-TOF analysis followed by homology search revealed that this protein could be heat shock cognate 70 (HSC 70). Anti-HSC 70 antibodies blocked CHIKV entry into C6/36 cells in a dose-dependent manner. IFA and flow cytometry analysis demonstrated HSC 70 localization on C6/36 cell surface. Co-IP experiments confirmed the interaction between HSC 70 and CHIKV envelope. Quercetin- and YM-01-treated C6/36 cells exhibited dose-dependent infection inhibition. CONCLUSION: HSC 70 serves as a putative CHIKV receptor on C6/36 cells.
BACKGROUND/AIMS: The study aimed to describe human papillomavirus (HPV) 58 genetic variability in E6 and E7 oncogenes from women in southeast Mexico and their phylogenetic relationships with the sequences from other geog...BACKGROUND/AIMS: The study aimed to describe human papillomavirus (HPV) 58 genetic variability in E6 and E7 oncogenes from women in southeast Mexico and their phylogenetic relationships with the sequences from other geographical regions. METHODS: The E6-E7 region was amplified by nested PCR, and sequenced for identification of polymorphisms, phylogenetic trees construction, and haplotype and fixation tests. RESULTS: HPV58 positive samples were obtained from a repository, 54 were amplified, 47 sequences for the E6 gene, and 51 sequences for the E7 gene were obtained. Fifteen new E6 mutations were found; the most frequent were G279T (G57V; 29.78%), T249G (F47C; 34.04%), and A270G (Y54C; 34.04%), and previously reported c307t (63.82%). For E7, 17 known mutations were found, the most frequent were C632T (T20I), 35.30%, G760A (G63S), 35.30%, and t744g 74.50%. No significant association with the severity of the lesions was found. The polytomy in the E6 tree did not allow proposing phylogenetic relationship, and E7 tree presented defined branches. All sequences were presumably A lineage, most closely related to A1 and/or A3 sublineage. HPV58 variants are not specific for a geographical area. Population and fixation analyses suggest a possible Asian origin of HPV58 from Yucatan. The most frequent E7 haplotype in Yucatan groups with other populations of the world. CONCLUSION: The genetic variability of HPV58 from Mexico was described for the first time. E7 was more conserved than E6. New mutants present exclusively in Yucatan were identified.
OBJECTIVE: The study was conducted to analyze changes in HA and NA genes of pandemic pH1N1 strains, collected from North Indian tertiary care hospital during 2015 and studied the nucleotide change since 2009. Differences...OBJECTIVE: The study was conducted to analyze changes in HA and NA genes of pandemic pH1N1 strains, collected from North Indian tertiary care hospital during 2015 and studied the nucleotide change since 2009. Differences in clinical features of cases positive and negative for influenza viruses were also studied. METHODS: All samples referred for H1N1 testing, were tested for influenza viruses. Randomly selected 25 strains of pH1N1 were studied for nucleotide sequences of HA & NA gene. The nucleotide changes occurring since 2009 were studied by mutational and phylogenetic analysis. Clinical details of cases were recorded and analysed. RESULTS: A total of 3319 cases of acute respiratory infections (ILI/SARI) were tested for influenza viruses during Jan to April 2015, of which 815 cases tested positive for pH1N1. Nucleotide variation of 2015 strains, from influenza A/California/07/2009 strain at HA1 and NA1 gene was 1.9% and 3.8% respectively. Both HA1 and NA1 coding sequence showed eight mutations. Four of HA1(K180Q, S202T, S220T, and A273T) and NA1 (N200S, V241I, N248D, and N270K) mutations were observed in all pH1N1 study strains. CONCLUSIONS: Strains of pH1N1 isolated during year 2015 diverged from previously circulating strains. Their association with severity of illness needs to be further studied.
In 2017, numerous cases of acute haemorrhagic conjunctivitis (AHC) were reported in the Caribbean and in South America. Preliminary reports identified adenoviruses and enteroviruses in some patient samples but, until now...In 2017, numerous cases of acute haemorrhagic conjunctivitis (AHC) were reported in the Caribbean and in South America. Preliminary reports identified adenoviruses and enteroviruses in some patient samples but, until now, none of the etiologic agents have been fully characterized. We report the full-length genomic sequences of 4 coxsackievirus A24 (CV-A24) isolates collected from AHC patients in French Guiana during this outbreak (May and June 2017). These isolates are very closely related and belong to the genotype IV of CV-A24 variant, which consists of strains sampled worldwide during AHC outbreaks in the 2000s and 2010s. No recombination events were detected within the genomic sequences, indicating that members of this genotype have continuously circulated worldwide for more than 10 years without undergoing recombination with other enteroviruses. This unusual trait could be due to their ocular tropism that could impede genetic exchanges between these viruses and other enteroviruses, which replicate mainly in the gut.
Abdel-Moneim AS, Varma A, Pujol FH
… +11 more, Lewis GK, Paweska JT, Romalde JL, Söderlund-Venermo M, Moore MD, Nevels MM, Vakharia VN, Joshi V, Malik YS, Shi Z, Memish ZA
OBJECTIVES: Kaposi sarcoma-associated herpesvirus (KSHV) glycoprotein B (gB) is expressed on the viral envelope as well as on the cytoplasmic membrane of infected cells. In the current study, we aimed to decipher the imp...OBJECTIVES: Kaposi sarcoma-associated herpesvirus (KSHV) glycoprotein B (gB) is expressed on the viral envelope as well as on the cytoplasmic membrane of infected cells. In the current study, we aimed to decipher the impact of membrane-associated gB on adhesion and migration of cells via modulating the expression of cytokines. METHODS: A combination of polymerase chain reaction array, cell adhesion assay, and wound-healing migration assay was conducted to study the influence of the gB-induced cytokines on cell adhesion and migration. RESULTS: Membrane-associated gB was demonstrated to significantly upregulate the expression of IL-1β and TNF-α. Elevated levels of these cytokines were observed in conditioned medium (CM) collected from gB-expressing cells (gB-CM) compared to CM collected from untransfected cells or cells transfected with empty vector. KSHV gB-induced IL-1β and TNF-α play a role in the ability of gB-CM to mediate cell adhesion while inhibiting migration. CONCLUSION: Our results provide novel evidence that demonstrates full-length gB expressed on cell membrane to mediate adhesion and inhibit migration of cells not only by autocrine mechanism mediated by RGD-based interactions [Hussein et al.: BMC Cancer 2016; 16: 148], but also by paracrine mechanism mediated by gB-induced IL-1β and TNF-α.
OBJECTIVES: The objective of this study was to understand natural disease progression in infant CD1 mice after the bite of Aedes aegypti mosquitoes infected by the Zika virus (ZIKV, MR-766 strain). METHODS: A. aegypti mo...OBJECTIVES: The objective of this study was to understand natural disease progression in infant CD1 mice after the bite of Aedes aegypti mosquitoes infected by the Zika virus (ZIKV, MR-766 strain). METHODS: A. aegypti mosquitoes were experimentally infected with ZIKV MR-766 strain via the oral feeding route. Infected mosquitoes were allowed to feed on infant CD1 mice. Sick mice were euthanized, and their organs were collected and subjected to real-time RT-PCR, histo-pathology, and immunohistochemistry. RESULTS: Clinical symptoms appeared in mice after 4-5 days of being bitten by mosquitoes, following which they were euthanized. Real-time RT-PCR analysis showed the presence of viral RNA in various organs such as the brain, liver, kidney, spleen, lungs, and intestines of the mice. The brain tissue specimens showed higher viral loads as determined by threshold values (Ct value) in the real-time RT-PCR assay. Histopathological and immunohistochemistry studies also revealed the presence of the virus and associated lesions in the brain, indicating that ZIKV shows tropism for neuronal tissue. CONCLUSIONS: This study demonstrates ZIKV pathogenesis in infant CD1 mice and that these mice are highly susceptible to natural infection with this ZIKV strain.
AIMS: This study describes an immunoassay to detect anti-torque teno virus (TTV) antibodies using a peptide obtained from expression of the N22 region of TTV genotype 2. METHODS: The N22 region (∼500 bp) of TTV genotype...AIMS: This study describes an immunoassay to detect anti-torque teno virus (TTV) antibodies using a peptide obtained from expression of the N22 region of TTV genotype 2. METHODS: The N22 region (∼500 bp) of TTV genotype 2 was cloned in a pET-28a(+) vector and expressed in ZYM-5052 autoinduction medium. Following metal affinity chromatography, a purified polypeptide was used as an antigen for the development of an immunoassay to detect anti-TTV antibodies in human sera. RESULTS: Recombinant protein (∼25-kDa) was obtained after 24 h of incubation at 25°C in ZYM-5052 autoinduction medium. A blot assay developed using this polypeptide as an antigen and TTV-positive sera as the primary antibody produced a distinct spot on the nitrocellulose membrane. Serum samples from 36 of 42 patients with renal disease and 29 of 48 patients with liver diseases produced a positive signal using this immunoassay. Simultaneously, 18 of 48 healthy controls were also detected to be positive for anti-TTV antibodies. These results were found to be comparable with TTV detection using PCR, and the assay showed a high sensitivity and specificity (i.e., 97.44 and 91.67%, respectively). Moreover, this assay could detect TTV infection irrespectively of the genotype, including cases of mixed infection. CONCLUSION: The present immunoassay using the N22 expression product may be used as an alternative to PCR to detect TTV infection in large populations.
Slovic A, Kosutic-Gulija T, Santak M
… +7 more, Ivancic-Jelecki J, Jagusic M, Ljubin-Sternak S, Mlinarić-Galinović G, Vilibić-Čavlek T, Tabain I, Forcic D
BACKGROUND: The families Paramyxoviridae and Pneumoviridae comprise a broad spectrum of viral pathogens that affect human health. The matrix (M) protein of these viruses has a central role in their life cycle. In line wi...BACKGROUND: The families Paramyxoviridae and Pneumoviridae comprise a broad spectrum of viral pathogens that affect human health. The matrix (M) protein of these viruses has a central role in their life cycle. In line with this, molecular characteristics of the M proteins from variable viruses that circulated in Croatia were investigated. METHODS: Sequences of the M proteins of human parainfluenza virus (HPIV) 1-3 within the family Paramyxoviridae, human metapneumovirus (HMPV), and human respiratory syncytial virus from the family Pneumoviridae were obtained and analyzed. RESULTS: M proteins were very diverse among HPIVs, but highly conserved within each virus. More variability was seen in nucleotide sequences of M proteins from the Pneumoviridae family. An insertion of 8 nucleotides in the 3' untranslated region in 1 HMPV M gene sequence was discovered (HR347-12). As there are no samples with such an insertion in the database, this insertion is of interest and requires further research. CONCLUSION: While we have confirmed that M proteins were conserved among individual viruses, any changes that are observed should be given attention and further researched. Of special interest is inclusion of HPIV2 M proteins in this analysis, as these proteins have not been studied to the same extent as other paramyxoviruses.
AIMS: To confirm the different characteristics of genotype-specific and common neutralizing epitopes of hepatitis E virus (HEV). METHODS: A competitive binding assay was established with known genotype-common neutralizin...AIMS: To confirm the different characteristics of genotype-specific and common neutralizing epitopes of hepatitis E virus (HEV). METHODS: A competitive binding assay was established with known genotype-common neutralizing monoclonal antibodies (mAbs) 3G1 and 5G5 as well as genotype-specific neutralizing mAbs 2B1 and 4C5. HEV ORF2 recombinant p166W01 derived from genotype 1 and p166Chn derived from genotype 4 were used as coated antigens, to determine whether the mAbs recognize independent, similar, or overlapping epitopes. mAbs were produced, purified, and conjugated with horseradish peroxidase (HRP). HRP-conjugated 2B1 could react only with p166W01 but not p166Chn, HRP-conjugated 4C5 could react only with p166Chn but not p166W01, while HRP-conjugated 3G1 and 5G5 could react both with p166W01 and p166Chn. Thus, competitive binding assays were performed successively using p166W01 and p166Chn antigen. RESULTS AND CONCLUSION: The results of competitive binding assays revealed that the binding of HRP-conjugated 2B1 to p166W01 could not be inhibited by 5G5 or 3G1. Similarly, the binding of HRP-conjugated 4C5 to p166Chn could not be inhibited by 5G5 or 3G1. However, the mAbs 5G5 and 3G1 blocked each other's binding to p166W01 and p166Chn, suggesting that common and genotype-specific neutralizing mAbs recognize independent epitopes.
OBJECTIVE: Since its discovery, Aichivirus (AiV) A has been detected, with an incidence of 0.9-4.1%, primarily when studying outbreaks of diarrhea in children or young adults. In this paper, we report the first detection...OBJECTIVE: Since its discovery, Aichivirus (AiV) A has been detected, with an incidence of 0.9-4.1%, primarily when studying outbreaks of diarrhea in children or young adults. In this paper, we report the first detection of AiV in Piedmont, Italy, in pediatric patients. METHODS: A total of 159 fecal specimens (from 96 males and 63 females) previously screened for rotaviruses, adenoviruses, noroviruses, human parechoviruses, saliviruses, and sapoviruses were collected from infants and children with acute gastroenteritis. RESULTS: The most commonly detected virus was norovirus GII (33.80%), fol lowed by rotavirus (21.30%), astrovirus (18.87%), boca virus (13.92%), sapovirus (10.90%), parechovirus (8%), norovirus GI (6.70%), adenovirus (1%), and salivirus (0.52%). Real-time polymerase chain reaction detected AiV A in 1 (0.62%) case subjects. AiV A was detected in monoinfection only in January. CONCLUSIONS: Our results indicate that AiV may be associated with a limited number of diarrhea cases in pediatric patients.
BACKGROUND AND AIMS: An acute hepatitis, caused by hepatitis E virus (HEV), is a significant global health concern, especially in developing countries. HEV has 1 serotype and 8 genotypes, which are further divided into s...BACKGROUND AND AIMS: An acute hepatitis, caused by hepatitis E virus (HEV), is a significant global health concern, especially in developing countries. HEV has 1 serotype and 8 genotypes, which are further divided into subtypes. Despite the availability of sporadic cases and outbreak data from India, specific information regarding HEV epidemiological data is lacking from central India. This study was conducted to understand epidemiological and molecular features of HEV in central India. METHODS: In this 3-year study conducted from July 2012 to June 2015, IgM ELISA was used for the diagnosis of suspected HEV cases. For identifying the genotype, nRT PCR was conducted and the PCR products were sequenced and analysed. Clinical and demographic data were analysed using statistical tools to highlight the trends. RESULT: Out of 1,369 suspected cases, 341 (24.9%) were positive for HEV. The positivity was significantly higher in males (69.2%) and in the age group of > 15-45 years (72.5%). The HEV cases peaked during the summer. Subtypes 1a and 1f of genotype 1 were detected in the area during the study period. CONCLUSION: HEV is a major aetiological agent of viral hepatitis in central India with adults and males at higher risk of infection. Two subtypes of the virus were detected in the region. Continuous serological surveillance and molecular monitoring will help to understand the epidemiology of HEV infection, outbreak mitigation and aid in providing treatment.
OBJECTIVES: The primary replication protein, HPV E1, has been shown to play a role in mitigating host defence and disrupting normal cell cycle processes, leading to the development of cancer. This study investigated the...OBJECTIVES: The primary replication protein, HPV E1, has been shown to play a role in mitigating host defence and disrupting normal cell cycle processes, leading to the development of cancer. This study investigated the expression profile of HPV16 E1 in various stages of cervical cancer development and the factors that control E1 expression. METHODS: One hundred and twenty-four HPV16-positive cervical samples ranging from normal to CIN 1, CIN 2/3, and SCC lesions were studied. E1 mRNA expression was determined by ddPCR. Methylation of promoters p97 and p670 was quantified by pyrosequencing, while PCR, qPCR, and sequencing were used to determine the physical state and variations of the HPV16 E1 genome. RESULTS: Increased E1 mRNA expression related to disease progression (normal 0.18, CIN 1 0.41, CIN 2/3 0.65, and SCC 0.79) was demonstrated with a significant positive correlation (r = 0.661, p = 0.019). No association between physical state and E1 expression was found. Methylation of p97 and p670 promoters showed significant elevation in SCC compared to normal samples. Only 4.2% showed genomic variations of HPV16 E1 63-bp duplication. CONCLUSION: E1 may play a role in cancer development. The detection of E1 mRNA and promoter methylation may be useful as cancer prognostic markers.
OBJECTIVE: This study aims to provide a molecular and epidemiological characterization of bovine papillomavirus (BPV) infections in Iraq. METHODS: The present study focuses on identifying BPV based on clinical and epidem...OBJECTIVE: This study aims to provide a molecular and epidemiological characterization of bovine papillomavirus (BPV) infections in Iraq. METHODS: The present study focuses on identifying BPV based on clinical and epidemiological manifestations, histopathological examinations, and polymerase chain reactions (PCR). Samples were collected from 163 animals suffering from cutaneous bovine papillomatosis, including 129 females (79.14%) with an age range of 16-40 months and 34 males (20.85%) with an age range of 17-29 months. RESULTS: The incidence rate was significantly higher in females than in males. The most commonly affected sites were the teats and neck, though warts were found in other areas of the body. Histological sections were diagnosed as fibropapilloma. PCR results showed that 80.13% of the extracted papilloma DNA samples corresponded to the BPV-1 genotype. Furthermore, 7.94% of the samples showed a mixed infection of BPV-1 and BPV-13. While, 40.63% of the extracted DNA blood samples showed 2 DNA fragments corresponding to both genotypes BPV-1 and BPV-2. CONCLUSIONS: This study confirmed the presence of BPV-1, BPV-2, and BPV-13, which belong to the Deltapapillomavirus genera, for the first time in the DNA of Iraqi cattle. Understanding BPV diversity and epidemiology is of critical importance for starting prevention strategies.
BACKGROUND: The cytomegalovirus (CMV) UL55 gene encodes for a glycoprotein implicated in virus pathogenesis. Based on UL55 polymorphism, CMV has been divided into 4 genotypes. Previous studies investigated the possible r...BACKGROUND: The cytomegalovirus (CMV) UL55 gene encodes for a glycoprotein implicated in virus pathogenesis. Based on UL55 polymorphism, CMV has been divided into 4 genotypes. Previous studies investigated the possible role of genotypes in the clinical outcome of infection in different categories of patients; however, few data are available, particularly in the transplant setting and Italian case records. METHODS: Phylogenetic analysis through a maximum likelihood tree was used to evaluate the prevalence and distribution of CMV genotypes in whole blood specimens from 47 transplant patients and investigate the relation with demographic and clinical features. RESULTS: Overall, 40.4% of patients were classified as single genotype (12.8% gB1, 23.4% gB2, 4.2% gB3); mixed genotypes were detected in 59.6%. Genotype 4 was detected only in mixed cases. In comparison to single genotypes, mixed genotypes were more frequently associated with a higher duration of DNA viremia and higher peak viral load. CONCLUSIONS: Mixed infections seem to be prevalent in Italian transplant patients; it is likely that mixed infections are more difficult to control by immunological response in comparison to single genotype infections. In this context, the genetic profile of infecting viruses and relation to clinical outcome should be investigated, also taking into account the CMV-specific cellular immune response.
OBJECTIVE: Human papillomavirus (HPV) vaccination is currently not included in the national vaccination program in Iran. Regional data on the distribution of HPV types in women are important as they can predict the impac...OBJECTIVE: Human papillomavirus (HPV) vaccination is currently not included in the national vaccination program in Iran. Regional data on the distribution of HPV types in women are important as they can predict the impact of currently available vaccines and help health policy makers to consider all the possibilities with regard to HPV vaccination. METHODS: A total of 1,218 Iranian women with normal cervical cytology were included in this study. The presence of the HPV genome was investigated in all specimens by PCR assay, and all HPV-positive samples were genotyped. RESULTS: Totally, HPV was detected in 88 samples (7.2%). According to different geographical regions, the HPV prevalence varied: the highest HPV prevalence was observed in the North (11.7%) and the lowest in the Center (4.5%) of Iran, and this difference reached a statistically significant level (p < 0.05). In this study, the most frequent HPV types were HPV 16, 18, 66, and 11, representing 63.8% of all HPV infections. CONCLUSION: Based on this study, it is estimated that HPV vaccines could have a great impact on the prevention of cervical cancer in Iran. This study highlights the necessity of introducing educational programs in high schools, robust screening programs, and vaccination in Iran.
Water, a frequent vehicle for the transmission of viruses, may permit their survival, but many environmental factors will have an adverse effect on the viral population. Risk evaluation requires identification of these f...Water, a frequent vehicle for the transmission of viruses, may permit their survival, but many environmental factors will have an adverse effect on the viral population. Risk evaluation requires identification of these factors and assessment of the inactivation rate of infectious viruses. A higher temperature means a faster reduction of the viral population, as do increased sunlight, higher antimicrobial concentration, or higher oxygen levels. Another documented impact is linked to the presence of indigenous microbial populations: virus survival is higher in sterile water. Environmental factors inactivate viruses through direct or indirect action on one part of the viral structure: genome, capsid, or envelope if present. Viral populations also have resistance mechanisms, generally involving physical shielding from adverse effects; such protective behaviors include aggregation, adhesion, or internalization inside living structures. Because of these phenomena, inactivation kinetics may deviate from traditional log-linear shapes. It is therefore important to account for all factors that may impact on survival, to carefully design experiments to ensure sufficient data, and to select the right modelling approach. Comparison between studies is difficult. It is suggested that laboratory studies include standard conditions of water, and analyze the impact of different factors as precisely as possible. Larger studies in natural environments, though more difficult, are also much needed.