Journal of Medical Microbiology and Infectious Diseases
Volume:8 Issue: 2, Spring 2020

Leishmaniases are tropical diseases caused by various types of intracellular protozoan species of the genus Leishmania. The infection is transmitted to vertebrate hosts by the infective bite of female sandflies. Depending on the location of the parasite in mammalian tissues and Leishmania species, leishmaniasis presents at least three primary clinical forms: visceral (VL), cutaneous (CL), and mucocutaneous (MCL). Iran is one of the significant endemic areas for CL in Asia. Here, we comprehensively reviewed the literature published from 2009 to 2019 and focused on the distribution, clinical aspects, causatives agents, reservoirs, and vectors of CL and VL in different parts of North Khorasan Province, northeast of Iran. North Khorasan Province in northeastern Iran is one of the principal foci of CL, but VL is just known as an endemic parasitic disease in some areas of this province. Based on a comprehensive literature search on studies published from 2009 to 2019, distribution, causatives agents, reservoirs, and vectors of CL and VL in different parts of North Khorasan Province were determined. Zoonotic cutaneous leishmaniasis )ZCL( due to Leishmania major is the main form of CL in this province. The principal animal reservoir hosts of the infection are rodents and Ph. sergenti is the most predominant species. VL, caused by Leishmania infantum, occurs in some parts of the province, and wild canines were confirmed as reservoirs.

Rasoul Pournaki (1921-2008), a prominent researcher, worked with the Pasture Institute of Iran from 1948 to 1978. He served meritoriously to control infectious diseases in Iran. His main research fields were the plague, relapsing fever, and poliomyelitis. He was the Director of Epidemiology and Virology Departments in the Pasteur Institute of Iran. This paper aims to appreciate his scientific contributions in control of infectious diseases by reviewing his notable services and studies.

The emergence of extended-spectrum β-lactamase (ESBL) and carbapenem-resistant Enterobacteriaceae, especially Klebsiella pneumoniae isolates, has become a severe concern worldwide. This study aimed to determine the prevalence of blaVIM and blaNDM genes among K. pneumoniae isolates.  

One hundred-eighty-one K. pneumoniae isolates were obtained from different clinical specimens of patients hospitalized at Firoozgar hospital, Tehran, Iran. The isolates were identified by standard biochemical tests, and their identity was confirmed by Vitek 2 (bioMérieux, France), a fully automated system for bacterial identification. The isolates were subjected to antimicrobial susceptibility testing and screened for ESBL by double-disc synergy test (DDST) and modified Hodge test (MHT) for the detection of carbapenemase. PCR was also used to detect the presence of blaVIM and blaNDM resistance genes in the isolates.

The Vitek 2 system confirmed the biochemical test results. The highest and lowest rates of resistance to antibiotics belonged to cefepime (83.9%) and imipenem (55.2%).  Eighty-six and 100 isolates showed to produce ESB and KPC by DDST and MHT, respectively. About 71% and 97% of the 100 isolates were positive for blaVIM and blaNDM genes, respectively.

The high rate of ESBL- and KPC-producing K. pneumoniae isolates in our hospital setting revealed resistance to conventional antibiotics, which limit our options in choosing appropriate antimicrobials. Although the management of infections associated with these organisms is challenging, it is essential to control such strains to prevent the outbreak.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral zoonosis with a considerable fatality rate. The virus is mainly transmitted to humans and animals through the bites of infected hard ticks belonging to the genus Hyalomma. This study aimed to determine the prevalence of CCHFV in ticks in Shahr-e Ray city, one of the meat supplier counties in Tehran Province, Iran.

A molecular survey was carried out on collected ticks from sheep in slaughterhouses and husbandries of Shahr-e Ray city, during 2016-17. The ticks were identified using taxonomic characteristics, and the presence of CCHF virus RNA was investigated using an RT-PCR amplifying a 536 bp of the small segment of the viral genome.

The results of this study showed that the Hyalomma ticks were the dominant species in Shahr-e Ray slaughterhouses and husbandries. In none of the assayed ticks, RT-PCR detected CCHFV RNA.

A considerable tick infestation with members of genus Hyalomma, among sheep in Shahr-e Ray slaughterhouses and husbandries, indicates the vulnerability of this county of tick-borne infections outbreaks such as CCHF. Therefore, applying acaricides and other preventive strategies should be adopted to control the tick population in Shahr-e Ray.

Cryptococcus neoformans is an encapsulated fungal pathogen that causes life-threatening meningoencephalitis in immunocompromised patients. This yeast secretes several potent immunogenic proteins by secretory vesicular mechanisms, such as HSP70 chaperone.

The PCR-amplified HSP70 gene was cloned into a PET-28a(+) expression vector. The purified recombinant HSP70  (rHSP70) was evaluated by western blotting using an anti-His Tag-HRP antibody and then used for immunization of a rabbit. The serum of the immunized rabbit was tested against the whole lysate of C. neoformans in ELISA.

The antibodies in the rabbit’s serum recognized lysate of C. neoformans yeast. The highest antibody levels were achieved after the third booster injection.

The rHSP70 showed to be a reliable candidate for the designing and development of an ELISA kit for early detection of cryptococcosis, and to screen a large number of specimens.

Coronavirus infectious disease 2019 (COVID-19) is a viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Pathogen-associated molecular patterns (PAMPs) can be detected by host pattern-recognition receptors (PRRs) expressed in inherent immune cells. The polymorphisms in PRRs leads to different recognizing and immune responses against viral infections.

Single-nucleotide polymorphisms of PRRs, minor allele frequency (MAF), and their geographical distribution were obtained from the Ensembl genome database. Interaction between the common polymorphic forms of PRRs (including TLR3, TLR7, RIG-1, and MDA-5) and SARS-CoV-2 virus genome (dsRNA) were predicted using the hybrid protein-RNA docking algorithm HDOCK server. Also, the global distribution of common SNPs and their MAFs were statistically analyzed using SPSS, ver.16.

The wild-type TLR3 and TLR3 SNP rs73873710 had the same docking energy score (-330.48 kcal/mol), and had lower docking energy scores compared to the other two SNPs, rs3775290 and rs3775291 (-301.42 and -295.81 kcal/mol, respectively). TLR7 SNP rs179008 had a higher docking energy score (-423.03 kcal/mol), comparing to the wild-type TLR7 (-445.46 kcal/mol). Also, there was a statistically significant direct relationship between MAF of TLR3 SNP rs3775290 and rs3775291 with SARS-CoV-2 prevalence (P=0.021 and P=0.023, respectively) and prevalence/population ratio of COVID-19 (P=0.026 and P<0.001, respectably).

Wild-type TLR3 and TLR3 SNP rs73873710 can recognize the SARS-CoV-2 dsRNA genome through a better performance compared to TLR3 SNP rs3775290 and TLR3 SNP rs3775291. Therefore, our in-silico study established that PRRs SNPs are associated with antiviral responses against SARS-CoV-2.

Canine zoonotic visceral leishmaniosis (VL) caused by Leishmania infantum has been reported from 20 out of 31 provinces in Iran. In 2013, 3.95% of dogs in Hamedan Province showed anti-L. infantum antibodies by indirect ELISA method. In 2018, we reevaluated L. infantum infection among stray dogs in the same region.

From June to November 2018, blood sera from 180 stray dogs in Hamedan and the outskirts were examined for the presence of anti-L. infantum antibodies using the same ELISA kit employed in the previous study.

The ELISA detected anti-L. infantum antibodies in blood sera of 19 dogs (10.56%, 95% CI: 6.18–14.94). Infected dogs were significantly older than non-infected dogs (p=0.048) with an odds ratio of 1.02 (p=0.02) between age and infection, implying that the odds of infection increased 2% with each month of age. Seropositivity rate was 11.21% in females and 11.11% in males with no significant difference between the two sexes (p=1). The odds of infection in female dogs were 1.01 compared to that in males.

The seroprevalence rate of L. infantum infection in stray dogs in this study showed an increase compared with 2013 (10.55% vs. 3.95%). An increase in antibodies against L. infantum in dogs of Hamedan and the presence of competent vectors for transmission of the parasite in the region makes the transmission of VL possible. Further PCR-based studies are required to confirm the infection in the infected dogs in sand flies.