* Sweden registers more than 4,000 new COVID cases
* Hospitalisations mount amid pandemic resurgence
* Swedish PM self-isolating (Adds details, quotes)
STOCKHOLM, Nov 5 (Reuters) - Sweden, whose pandemic strategy of avoiding lockdowns has gained international attention, reported a record increase in new COVID-19 cases on Thursday as health officials said it was seeing a marked rise of patients in intensive care.
Sweden registered 4,034 new coronavirus cases, health agency data showed, the latest in a string of records set in recent days amid a pandemic resurgence that has struck the country later than many other parts of Europe, but which now appears to be rapidly gaining momentum.
The Health Agency has said the outbreak was likely more severe during the spring when Sweden periodically suffered some of Europe's highest per capita death tolls though limited testing at the time had meant many infections went undetected.
"There is continued increase in the number of cases in all regions except one," said Karin Tegmark Wisell, head of the microbiology department at the agency.
"We are now also beginning to see a fairly significant increase on the number of intensive care patients."
The intensifying outbreak has seen Sweden tighten the mostly voluntary recommendations on which it relies across much of the country and Tegmark Wisell said the percentage of positive tests had climbed to 9.7% last week from 5.6% the week before.
Earlier on Thursday, Swedish Prime Minister Stefan Lofven said he was self-isolating and getting tested after he learned a person close to him had met someone who was later confirmed to have COVID-19.
On Thursday, 90 COVID-19 patients were receiving intensive care at Swedish hospitals, 19 more than on Wednesday, while a further 661 were being treated in other modes of care.
Sweden registered 5 new deaths, taking its death toll during the pandemic to 6,002. Sweden's death rate per capita has been several times higher than Nordic neighbours but lower than some larger European countries, such as Spain and Britain. (Reporting by Johan Ahlander and Niklas Pollard; editing by Niklas Pollard)
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