From a worldwide perspective, porcine parvovirus (PPV) and porcine reproductive and respiratory syndrome virus (PRRSV) are the most common viral causes of porcine reproductive failure. A typical epidemic of PPV-induced reproductive failure is presented as an increased number of mummified fetuses and sometimes, entire litters are mummified. If infection with PPV is very early in gestation, the n...

We examined 10,025 respiratory samples collected for 4 years (2001-2004) and found a 7.1% average annual incidence of human metapneumovirus. The epidemic peak of infection was late winter to spring, and genotyping showed a change in predominant viral genotype in 3 of the 4 years.

With more emphasis being put on global infectious disease monitoring, viral genetic data are being collected at an astounding rate, both within and without the context of a long-term disease surveillance plan. Concurrent with this increase have come improvements to the sophisticated and generalized statistical techniques used for extracting population-level information from genetic sequence dat...

Background:Today, with the coronavirus pandemic, the governments and international institutions are rapidly taking various approaches to infection control. In the meantime, the care of healthcare workers who are responsible for the health and treatment of patients is very important. The COVID-19 epidemic in China has achieved a great victory, and it is important to summarize the successful anti...

Epidemic keratoconjunctivitis is usually caused by infection with an adenovirus, generally type 8 (Hanna, Jawetz, Mitsui, Thygeson, Kimura, and Nicholas, I957). As this is a DNA virus it might be expected to respond to treatment with 5-iodo-2'-deoxyuridine (IDU) which acts by interfering with the normal synthesis of DNA, thus preventing replication of DNA-containing viruses (Herrmann, I 96 I; S...

The nature of clinical medicine is to focus on individuals rather than the populations from which they originate. This orientation can be problematic in the context of acute healthcare delivery during routine winter outbreaks of viral respiratory disease where an individuals likelihood of viral infection depends on knowledge of local disease incidence. The level of interest in and perceived uti...

In this paper, we propose a within-host HIV-1 epidemic model with cell-to-virus and cell-to-cell transmission. By mathematical analysis, we obtain the basic reproduction numberR0, which determines the viral persistence and the basic reproduction numberRcc 0 with respect to cell-to-cell transmission which is not strong enough, i.e., it is less than 1. If the basic reproduction number is less tha...

To reduce the risk of slip, grip force (GF) control includes a safety margin above the force level ordinarily sufficient for the expected load force (LF) dynamics. The current view is that this safety margin is based on the expected LF dynamics, amounting to a static safety factor like that often used in engineering design. More efficient control could be achieved, however, if the motor system ...

Recent data shows that HIV-1 is characterised by variation in viral virulence factors that is heritable between infections, which suggests that viral virulence can be naturally selected at the population level. A trade-off between transmissibility and duration of infection appears to favour viruses of intermediate virulence. We developed a mathematical model to simulate the dynamics of putative...

Recent studies of HIV RNA in infected individuals show that viral levels vary widely between individuals and within the same individual over time. Individuals with higher viral loads during the chronic phase tend to develop AIDS more rapidly. If RNA levels are correlated with infectiousness, these variations explain puzzling results from HIV transmission studies and suggest that a small subset ...