Epidemiological Surveillance of Viral Hemorrhagic Fevers With Emphasis on Clinical Virology

Abstract

This article will outline surveillance approaches for viral hemorrhagic fevers. Specific methods for surveillance of clinical samples will be emphasized. Separate articles will describe methods for surveillance of rodent-borne viruses (roboviruses) and arthropod-borne viruses (arboviruses). Since the appearance of hantaviruses and arenaviruses in the Americas, more than 30 different species in each group have been established, and therefore they have become the most frequently emerging viruses. Flaviviruses such as yellow fever and dengue viruses, although easier to recognize, are also more widely spread and therefore considered a very important public health issue, particularly for under-developed countries. On the other hand, marburgviruses and ebolaviruses, previously thought to be restricted to the African continent, have recently been shown to be more global. For many of these agents virus isolation has been a challenging task: trapping the specific vectors (mosquitoes and ticks), and reservoirs (rodents and bats), or obtaining the samples from suspected clinical human cases demands special protective gear, uncommon devices (respirators), special facilities (BSL-3 and 4), and particular skills to recognize the slow and inapparent cytopathic effects in cell culture. Alternatively, serological and molecular approaches have been very helpful in discovering and describing newly emerging viruses in many areas where the previous resources are unavailable. Unfortunately, in many cases, detailed studies have been performed only after outbreaks occur, and then active surveillance is needed to prevent viral dissemination in human populations.

Seroprevalence, cross antigenicity and circulation sphere of bat-borne hantaviruses revealed by serological and antigenic analyses

“…HV positive lung tissues (~100 mg/bat) were thoroughly ground with DMEM (500 μL/100 mg tissue) in a homogenizer and clarified by centrifugation at 5,000 g for 5 min. Following sterilization by passage through a 0.22 μm Millipore filter supernatants were incubated with BHK-21 cells as well as the HV-sensitive cell lines Vero and Vero E6 [56] (all stored in our laboratory) in 24-well plates. After incubation for 24 h at 37ºC, the cells were washed 2x with PBS, incubated in DMEM with 2% FBS for 14–21 days and observed daily for cytopathic effects (CPE).…”

Compendium: Management of Viral Hemorrhagic Fever (Viral Fever), Involving Its Pathogenesis

“…These illnesses are typically limited to the endemic regions where their hosts reside due to their zoonotic nature. Nevertheless, these illnesses are no longer exclusive to the regions where they originated due to rising human migration and greater globalization [4]. A collection of acute zoonotic illnesses known as viral hemorrhagic fevers (VHFs) have high fatality rates and are brought on by seven distinct virus families that can infect both people and animals.…”