Incidence of influenza virus-associated severe acute respiratory infection in Damanhour district, Egypt, 2013

The epidemiology, seasonality and risk factors for influenza virus infection remains poorly defined in countries such as Egypt. Between 1 January and 31 December 2013, we used surveillance data on patients hospitalized with severe acute respiratory infection in three Egyptian government hospitals in Damanhour district to estimate the incidence rate of laboratory-confirmed seasonal influenza. Samples were taken from 1727 of 1856 patients; of these, 19% were influenza virus positive. The overall incidence of influenza virus-associated SARI during the study period was estimated to be 44 cases per 100 000 person-years (95% CI: 39-48). The highest incidence of 166 cases per 100 000 person year (95% CI: 125-220) was observed in children aged 2 to 4 years. The incidence of influenza-virus associated SARI cases in pregnant women was estimated to be 17.3 cases per 100 000 person-years (95% CI: 6-54). Majority of influenza virus-associated SARI occurred in autumn and early winter, and influenza A(H3N2) virus predominated. This was the first ever description of the epidemiology of seasonal influenza in Egypt. However, additional works are needed for greater understanding of influenza burden in Egypt.

A new tobamovirus infecting tomato crops in Jordan

In this study, we completed the whole genome sequence of a new tobamovirus isolated from tomato plants grown in greenhouses in Jordan during the spring of 2015. The 6393-nt single-stranded RNA (ssRNA) genome encodes four proteins, as do other tobamoviruses: two replication-related proteins of 126 kDa and 183 kDa, a 30-kDa movement protein (MP) and a 17.5-kDa coat protein (CP). Phylogenetic analysis showed that this virus does not group with either the tomato mosaic virus (ToMV) or the tobacco mosaic virus (TMV) clades. Instead, it stems from a branch leading to the TMV clade. Analysis of possible recombination events between this virus and representative isolates of closely related tomato-infecting tobamoviruses showed that at least one region originated by recombination. We provide evidence that we have identified a new tobamovirus, for which we propose the name "tomato brown rugose fruit virus".

Effects of doxycycline on heartworm embryogenesis, transmission, circulating microfilaria, and adult worms in microfilaremic dogs

Tetracycline treatment of animals or humans infected with filariae that harbor Wolbachia endosymbionts blocks further embryogenesis, and existing microfilariae gradually die. This treatment also kills developing larvae and has a slow-kill effect on adult filariae, all presumably due to elimination of the Wolbachia. Also, Dirofilaria immitis microfilariae in blood collected from dogs up to 25 days after the last dose of doxycycline developed to infective L3 that were normal in appearance and motility in mosquitoes but did not continue to develop or migrate normally after subcutaneous (SC) injection into dogs. The present study was designed to determine whether heartworm microfilariae collected at later times after treatment would regain the ability to continue normal development in a dog. The study also was expected to yield valuable data on the effects of treatment on microfilariae and antigen levels and adult worms. The study was conducted in 16 dogs as two separate replicates at different times. A total of five dogs (two in Replicate A and three in Replicate B) infected either by SC injection of L3 or intravenous transplantation of adult heartworms were given doxycycline orally at 10mg/kg twice daily for 30 days, with three untreated controls. Microfilarial counts in the five treated dogs gradually declined during the 12-13 months after treatment initiation. Two dogs were amicrofilaremic before necropsy and three had 13 or fewer microfilariae/ml. Only one treated dog was negative for heartworm antigen before necropsy. Overall, treated dogs generally had fewer live adult heartworms than controls, and most of their live worms were moribund. All three control dogs remained positive for microfilariae and antigen and had many live worms. L3 from mosquitoes fed on blood collected 73-77 or 161-164 days after initiation of doxycycline treatments were injected SC into five dogs. None of the dogs injected with L3 from mosquitoes fed on blood from doxycycline-treated dogs were ever positive for microfilariae or antigen, and none had worms at necropsy; three control dogs were positive for microfilariae and antigen and had many live worms. These data indicate that doxycycline treatment of microfilaremic dogs gradually reduces numbers of microfilariae and blocks further transmission of heartworms. This latter effect should be highly effective in reducing the rate of selection of heartworms with genes that confer resistance to macrocyclic lactone preventives and microfilaricides. The data also suggest that doxycycline has a slow-kill effect on adult heartworms.

Transient tachypnea of the newborn: Is empiric antimicrobial therapy needed?

BACKGROUND

Transient tachypnea of the newborn (TTN) is a self- limited increase in the work of breathing in near- and full-term infants; it is attributed to a delay in the clearance of alveolar fluids. Prophylactic antibiotics are usually administered until blood cultures are reported negative for 48 hours.

OBJECTIVES

To prospectively compare outcomes of infants presented with classic TTN who were treated with or denied from intravenous antibiotics.

METHODS

A prospective cohort study was conducted on all infants admitted with classic TTN. Pre-set diagnostic criteria for classic TTN were applied in order to exclude other cases presenting with respiratory distress. Infants with classic TTN were stratified into two groups based on whether they received or did not receive antibiotics. The decision to administer antibiotics solely depended upon the style of the covering physician at the time of admission to the NICU. The following investigations were obtained from infants of both groups: blood culture, C-reactive protein, complete blood count, blood gas profile and chest X-ray.

RESULTS

A total of 15146 full-term infants were delivered during the study period; of them 923 were admitted to the NICU. Classic TTN was diagnosed in 168 infants; of them 106 (63%) received and 62 (37%) did not receive antibiotics. Two infants in the treated group and an infant in the non-treated group had microbiologically confirmed bacteremia. Infants in the treatment group stayed longer in the hospital (72 ± 6 vs. 48 ± 3 hrs). No recorded cases required readmission in either group.

CONCLUSIONS

With the application of strict criteria for classic TTN and the close observation in the NICU, the empiric use of antibiotics may be avoidable. Randomized controlled trials are needed to confirm the feasibility and safety of such approach.

Taurine for EPR dosimetry

EPR dosimetry is characterized by its non-destructive read-out and the possibility of dose archival. Here, taurine is proposed as a radiation dosimeter using EPR spectroscopy. The EPR spectrum of taurine was studied and assigned, and changes in the taurine EPR spectrum as a result of the change in both modulation amplitude and microwave power were quantified. For gamma radiation, the energy absorption coefficient and the collision mass stopping power of taurine were compared to the corresponding values of soft tissue and alanine, in addition to calculation of effective atomic numbers. The response of taurine to gamma radiation doses in the range from 0.1 to 50 kGy was investigated, as well as that in the range from 1.0 to 20.0 Gy using numerically enhanced EPR taurine spectra. Both response curves showed a linear behavior. In addition, the time dependence of radiation-induced radicals was studied for short (during the first 6 h after irradiation) and long (during about 3 months after irradiation) time periods, and a reasonable degree of stability of the taurine radicals was observed. It is concluded that taurine is a promising dosimeter, which is characterized by its simple spectrum, radical stability, and wide range of linear response to gamma radiation.