CHAPTER 16 Viral Infections
Neonatal and puppy-kitten mortality rates (animals dying before 1 year of age) are often used as clinical indicators of the general level of health in the community, including the level of vaccination that is used in the area (Table 16-1). Infectious diseases are a major threat to the health of neonatal animals and may contribute to the mortality rate. Neonatal puppies and kittens depend in large part on the presence of sufficient maternal immunity, which provides short-term, passive immunity to protect them against microbial pathogens in the neonates’ environment. The severity of clinical symptoms (disease) in puppies and kittens that may result from infectious microorganisms depends on several key factors (Box 16-1). In addition to current maternal passive immunity, they include preexisting maternal infection status, maternal and neonatal nutrition, neonatal thermoregulation, concurrent neonatal infections and parasitism, and hereditary defects of the immune system.
TABLE 16-1 Effects of population (herd) immunity* on neonatal puppy and kitten survival
Effects on | High survivability | Low survivability |
---|---|---|
Herd immunity | Increased | Decreased |
Maternal immunity | Increased | Decreased |
Colostral immunity | Increased | Decreased |
Maternal/cohort shedding | Decreased | Increased |
Survival of neonates | Increased | Decreased |
* Defined as 85% or greater of the population that are immune. Immunity is attained by regular vaccination boosters and/or continual boosters from natural infections from subclinical carrier animals.
BOX 16-1 Factors influencing the severity of clinical symptoms in puppies and kittens
Modified from Root Kustritz MV: Neonatology. In Root Kustritz MV (ed): Small animal theriogenology, St. Louis, 2003, Elsevier, p. 283.
Control of neonatal viral infections involves screening for preexisting infections and vaccination (when available) of the dam, minimizing potential exposure during critical periods (Table 16-2) and ensuring adequate colostral intake by the neonates (see Chapter 14). The critical periods are preconception, pregnancy, periparturient, and postnatal. The outcome of infection during these periods depends on previous individual animal immunity and viral challenge from the environment.
Specific Viral Diseases of Pediatric Canine Patients
Canine Parvoviruses (CPV-2, CPV-1)
CPV-2
Although there is no specific treatment for CPV-2, viral-bacterial enteritides generally consist of treating dehydration, sepsis, and acidosis/electrolyte imbalances. Intravenous balanced electrolyte solutions, systemic antibiotics (see Chapter 27), and antiemetic therapy may be indicated if vomiting is a significant component of the symptoms. Control measures include disinfection to reduce (dilute) the viral challenge load and immunization with modified live CPV-2 vaccines of adult dogs in the population and the susceptible puppies (Table 16-3). The role of immunization is twofold: the first is protection of individual puppies, and the second is to hyperimmunize adults to minimize viral shedding.
Canine Herpesvirus

Figure 16-1 The 6-week danger period in relationship to whelping and the various sources of CHV for neonatal infections.
(Redrawn from Diagnosis of canine herpetic infections. In Kirk’s current veterinary therapy X, 1989, Elsevier.)
You may also need

Full access? Get Clinical Tree

