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As part of further investigations into three linked haemorrhagic fever with renal syndrome (HFRS) cases in Wales and England, 21 rats from a breeding colony in Cherwell, and three rats from a household in Cheltenham were screened for hantavirus. Hantavirus RNA was detected in either the lungs and/or kidney of 17/21 (81%) of the Cherwell rats tested, higher than previously detected by blood testing alone (7/21, 33%), and in the kidneys of all three Cheltenham rats. The partial L gene sequences obtained from 10 of the Cherwell rats and the three Cheltenham rats were identical to each other and the previously reported UK Cherwell strain. Seoul hantavirus (SEOV) RNA was detected in the heart, kidney, lung, salivary gland and spleen (but not in the liver) of an individual rat from the Cherwell colony suspected of being the source of SEOV. Serum from 20/20 of the Cherwell rats and two associated HFRS cases had high levels of SEOV-specific antibodies (by virus neutralisation). The high prevalence of SEOV in both sites and the moderately severe disease in the pet rat owners suggest that SEOV in pet rats poses a greater public health risk than previously considered.

Breda, Nedela and Širáň (2005) classified the regular maps on surfaces of Euler characteristic $-p$ for every prime $p$. This classification relies on three key theorems, each proved using the highly non-trivial characterisation of finite groups with dihedral Sylow 2-subgroups, due to D. Gorenstein and J.H. Walter (1965). Here we give new proofs of those three facts (and hence the entire classification) using somewhat more elementary group theory, using without referring to the Gorenstein-Walter theorem.

We prove the existence of infinitely many orientably-regular but chiral maps of every given hyperbolic type {m, k}, by constructing base examples from suitable permutation representations of the ordinary (2, k, m) triangle group, and then taking abelian p-covers. The base examples also help to prove that for every pair (k, m) of integers with 1/k + 1/m ≤ 1/2, there exist infinitely many regular and infinitely many orientably-regular but chiral maps of type {m, k}, each with the property that both the map and its dual have simple underlying graph.

We prove the existence of infinitely many orientably-regular but chiral maps of every given hyperbolic type {m, k}, by constructing base examples from suitable permutation representations of the ordinary (2, k, m) triangle group, and then taking abelian p-covers. The base examples also help to prove that for every pair (k, m) of integers with 1/k + 1/m ≤ 1/2, there exist infinitely many regular and infinitely many orientably-regular but chiral maps of type {m, k}, each with the property that both the map and its dual have simple underlying graph.

Breda, Nedela and Širáň (2005) classified the regular maps on surfaces of Euler characteristic $-p$ for every prime $p$. This classification relies on three key theorems, each proved using the highly non-trivial characterisation of finite groups with dihedral Sylow 2-subgroups, due to D. Gorenstein and J.H. Walter (1965). Here we give new proofs of those three facts (and hence the entire classification) using somewhat more elementary group theory, using without referring to the Gorenstein-Walter theorem.