Immature (larval) forms of lepidopteran species (moths and butterflies) are the most common hosts, but these viruses have also been found infecting sawflies, and mosquitoes.

The earliest records of baculoviruses can be found in the literature from as early as the 16th century in reports of "wilting disease" infecting silkworm larvae.

Immature (larval) forms of lepidopteran species are the most common hosts, but these viruses have also been found infecting sawflies and mosquitoes.

[citation needed] Typically, the initial infection occurs when a susceptible host insect feeds on plants that are contaminated with the occluded form of the virus.

Viral transcription and replication occur in the cell nucleus and new BV particles are budded out from the basolateral side to spread the infection systemically.

During budding, BV acquires a loosely fitting host cell membrane with expressed and displayed viral glycoproteins.

The extensive lysis of cells frequently causes the host insect to literally disintegrate, thus the reason for the historic name "wilting disease".

The complete ODV-polyhedrin particles are resistant to heat and light inactivation, whereas the naked BV virion is more sensitive to environment.

The virus was originally isolated from the alfalfa looper (a lepidopteran) and contains a 134 kbp genome with 154 open reading frames.

[9] Using cryo–electron microscopy, it has been shown that the major capsid protein VP39 forms a covalently cross-linked helical tube protecting a highly compacted 134-kilobase pair DNA genome.

The ends of the tube are sealed by the base and cap substructures, which share a 126-subunit hub but differ in components that promote actin tail–mediated propulsion and nuclear entry of the nucleocapsid, respectively.

[9] The fold of VP39 is novel and is unrelated to those of major capsid proteins encoded by non-baculo-like dsDNA viruses that belond to realms Varidnaviria and Duplodnaviria.

This extension has a structural role as it projects away from the main body of the major capsid protein to form a interdimer disulfide bond between two Cys29 residues from neighboring VP39 strands in the nucleocapsid.

Although gp64 has variety of essential functions, it has been reported that gp64-null baculoviruses can be substituted with other viral glycoproteins such as Ld130, G-protein of Vesicular stomatitis virus.

[citation needed] Baculovirus expression in insect cells represents a robust method for producing recombinant glycoproteins or membrane proteins.

[citation needed] Members of the genus Heliothis—cosmopolitan insects that attack at least 30 food- and fibre-yielding crop plants—have been controlled by the application of Baculovirus heliothis.