Bovine ephemeral fever (BEF) also known as Three Day Sickness is an arthropod

Arthropod

An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...

 vector-borne disease of cattle and is caused by the Ephemerovirus virus of the Rhabdoviridae

Rhabdoviridae

Rhabdoviruses are viruses belonging to the family Rhabdoviridae, which is in the order Mononegavirales. The name is derived from the Greek rhabdos meaning rod referring to the shape of the viral particles. Rhabdoviruses infect a broad range of hosts throughout the animal and plant kingdoms...

family of virus. The Rhabdoviridae are a class V virus according to the Baltimore classification

Baltimore classification

The Baltimore classification, developed by David Baltimore, is a virus classification system that groups viruses into families, depending on their type of genome and their method of replication....

 of viruses. The BEF virus is a bullet or cone shaped virion which consists of a negative, single stranded RNA genome with a lipid envelope and 5 structural proteins. The envelope glycoprotein

Glycoprotein

Glycoproteins are proteins that contain oligosaccharide chains covalently attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. In proteins that have segments extending...

 G contains type-specific and neutralizing antigenic sites. Theres has been recent evidence which demonstrated that the BEF virus induces apoptosis

Apoptosis

Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...

 in several cell lines. It was however shown that apoptosis could be blocked by the caspase inhibitor (Z-VAD-fmk), indicating that bovine ephemeral fever virus induces caspase-dependent apoptosis in cultured cells.

Location

The virus has been found in tropical and subtropical regions of Asia, Africa and through eastern Australia.

Transmission

The virus is transmitted by an insect vector. The particular species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 linked to the virus are the biting midges Culicoides oxystoma and C. nipponensis.

Disease Characteristics

The characteristics of the disease are the sudden onset of fever

Fever

Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...

, stiffness

Stiffness

Stiffness is the resistance of an elastic body to deformation by an applied force along a given degree of freedom when a set of loading points and boundary conditions are prescribed on the elastic body.-Calculations:...

, lameness and nasal

Nose

Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes through the pharynx, shared with the...

 and ocular

Eye

Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...

 discharges. BEF often causes hypocalcaemia

Hypocalcaemia

In medicine, hypocalcaemia is the presence of low serum calcium levels in the blood, usually taken as less than 2.1 mmol/L or 9 mg/dl or an ionized calcium level of less than 1.1 mmol/L or 4.5 mg/dL. It is a type of electrolyte disturbance...

 which in turn generates clinical signs such as depression

Clinical depression

Major depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and by loss of interest or pleasure in normally enjoyable activities...

, cessation of rumination

Rumination

The term rumination , meaning "to chew the cud," is used in several contexts:-Digestive rumination:* In animals, rumination is a part of normal digestion, in which the animal brings up swallowed food , chews it, and swallows it...

, muscle tremors and constipation

Constipation

Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation...

.

Although the pathogensis of the disease is complex it seems clear that the host inflammatory responses, mediated by the release of cytokines, are involved in the expression of the disease.

Diagnosis

The virus can be isolated from blood and can be identified by immunofluorescence and immunostaining. Rising antibodies in two samples taken 2-4 weeks apart also indicate infection.

Treatment

Calcium borogluconate and NSAIDs

Non-steroidal anti-inflammatory drug

Nonsteroidal anti-inflammatory drugs, usually abbreviated to NSAIDs or NAIDs, but also referred to as nonsteroidal anti-inflammatory agents/analgesics or nonsteroidal Anti-inflammatory medicines , are drugs with analgesic and antipyretic effects and which have, in higher doses, anti-inflammatory...

often help to alleviate clinical signs, but rest is absolutely imperative, for a mimimum of one week or death can still occur.

Control

A vaccine is available in Japan but is very expensive which limits its use. Movement regulations are in place in several countries.